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Tydlig – Calculator Reimagined for iPad and iPhone

411 points by Istof 13y ago

cdcarter 13y ago
This looks great, for some uses, but I know myself (and a lot of my coworkers) would much prefer a beautiful iPhone calculator that behaves more like a 10-key/adding machine than an iPython notebook.
mwc 13y ago
The linked numbers are brilliant. Lacking the "in my head" math skills I should probably have, I regularly whip out Excel to solve the kind of use cases you can imagine from the linked numbers in the video.
jckt 13y ago
Graphing functionality on a phone reminds me of an old TI calculator. I really don't know why recent OSes (be it on PC, smartphone, tablet) always came with such feeble calculators. It's not like TI calculators are difficult to use. Sure if all you want is add/min/mul/div functionality the TI is essentially a traditional calculator, and then behind that you've got all these nifty graphing utilities. It's not like a graphing calculator app is going to be that difficult to program, or going to be large in size. But no, in 2013, vanilla OS installations are stuck with a calculator app that has less features than that of a computer a few million times less powerful. (Now I feel bad; bitching and complaining is against the Open Source Spirit). Edit: I do recall that OSX comes with something similar, except that not many people actually know of it (as far as I can tell, from my friends with OSX).
- Void_ 13y ago
  Bitching and complaining is good for products, makes them better. Don't know much about OSS spirit, but doesn't their work need any improvement??
  - jckt 13y ago
    By OSS spirit I meant that it's better to get coding than start complaining. But I see your point -- indeed we should do both, and plenty of it.
- shurcooL 13y ago
  On that note, iPad doesn't even have the iPhone Calculator app, and it's _impossible_ to get it (without hacking) because it's a built-in app; one you cannot remove nor acquire from the App Store. It's also missing Compass, Voice Memo and Passbook apps. Edit: Weather app too.
  - frik 13y ago
    yes weird, plus the weather app is missing too. What's the reasoning behind the decision? Was it Steve Jobs who decided that?
    - shurcooL 13y ago
      They just haven't created the full size iPad versions for them at this time. iOS 6/7 added some previously iPhone-only built-in apps.
    - cmelbye 13y ago
      I've always had a feeling that it's to differentiate iPad from iPhone. If they had the exact same apps, right down to a scaled up Calculator with gigantic buttons on the 10" display, it might make it less likely for consumers to think of iPad as a separate concept from iPhone. Calculator and Weather wouldn't really translate that well to a huge screen, anyways. And, of course, there are several great third-party apps to fill the void if you need them.
  - superuser2 13y ago
    Missing compass because the WiFi version does not contain a GPS or magnetic compass.
    - shurcooL 13y ago
      There is a cellular version of the iPad too.
- tolmasky 13y ago
  Just a musing: perhaps its considered not as valuable an investment to program since a (the?) primary market is students, and students are probably not allowed to use phones on tests for obvious reasons (internet connectivity, texting questions to each other, overall distraction). However, TI's are state approved or whatever.
  - fophillips 13y ago
    Never been allowed to use a TI for exams in the UK. I've only ever been allowed to use a Casio.
    - cmelbye 13y ago
      It's incredibly common for TI calculators to be allowed on exams in the United States. Several standardized tests specifically allow only TI calculators, along with a few others. I think GP's comment makes a lot of sense. Most students just aren't going to put the effort into learning how to use another graphing calculator program if they can't even use it in class.
    - asselinpaul 13y ago
      I am currently in Year 13 in London. You are definitely allowed TI in the mathematics exams (A-Levels). TI-89 is one of the only that is banned because of its CAS. Friends in the French system are allowed the TI 89 though.
      - burriko 13y ago
        Yep, I did Maths A-level in the UK back in the 90s, and a TI graphing calculator was basically a requirement for the exams.
        fophillips 13y ago
        Interesting, I wasn't allowed to use one in A-Levels or university exams.
      - 13y ago
- fredsted 13y ago
  Yep, Grapher is a nice app with an interesting history: http://en.wikipedia.org/wiki/Grapher http://en.wikipedia.org/wiki/Grapher
  - Someone 13y ago
    Does Grapher share any source with Graphing Calculator? I guess it might, given that Apple shipped Graphing Calculator with Mac OS before, and given Graphing Calculator's interesting early history (http://www.pacifict.com/Story/ http://www.pacifict.com/Story/) (I wonder how Apple negotiated that deal originally. I guess some lawyers spent quite some time arguing whose intellectual property it originally was. The programmers weren't paid by Apple, but worked at Infinite Loop)
- Someone 13y ago
  "It's not like a graphing calculator app is going to be that difficult to program" It is surprisingly hard to get something that produces reliable plots. It starts with getting something as simple as sin(1/x) or x/(x^2 + 5x + 1) to plot reasonably well, and gets harder from there soon (edit: if you want to complicate things, pick a function that is only defined on some numbers, such as sqrt(x^2 * sin(x^3 - x). Adding a pair of || around subexpressions also complicates things) For example, at https://www.desmos.com/calculator https://www.desmos.com/calculator (one of the top results from a google search) zooming in on sin(1/x) shows a plot that sometimes doesn't go up to 1.0 for values of x close to zero. Its plot is decent, but deceiving. And you will have to do those well, as the target audience of students encounters such functions every day. And the Mac OS X one is Grapher (http://en.wikipedia.org/wiki/Grapher http://en.wikipedia.org/wiki/Grapher)
- bane 13y ago
  It's depressing to me that the closest I can get to the TI-92+ I had in college is to emulate a TI-92+ on my computer or Android devices (actually on a tablet it's not too bad). My other options (Octave, Matlab, etc.) are way too heavy for what I want to do and require too much time to learn. They don't have that sort of pickup-and-use feature my old calculators used to have. I think it's the presence of most of the buttons I'm ever going to be interested in on the keyboard rather than having to figure out how to type something that means the same as an integral or some such. The discoverability of those buttons beats most modern software hands down. I also suspect that writing simple to use general purpose solvers and simplifiers for the things the TI calcs do (the CAS) is likely very hard. I remember putting even pretty complex physics equations with all sorts of trig functions and exponents and integrals and such in during college and it handled most of them without trouble and pretty printed the result.
  - csmuk 13y ago
    Ha I had a TI92 (not plus) a number of years ago. Weighed a ton - you could kill someone with it. Sold it and got an HP48GX after I discovered that you couldn't get the plus module for it in the UK for a reasonable price. Never looked back.
  - cstejerean 13y ago
    I miss my TI-92+ as well. It feels like an iPad has enough screen real estate to be able to simulate the same experience, and I was surprised that nobody has done it yet. Edit: looks like there are some good options for Android that actually emulate TI calculators, and apparently TI has Nspire for the iPad.
- robterrell 13y ago
  On OS X it's Graphing Calculator. See the amazing story behind it: http://www.pacifict.com/Story/ http://www.pacifict.com/Story/
  - axman6 13y ago
    I was just going to write this comment myself before checking to see if I'd been beaten. It's definitely one of the great stories of computer history.
userbinator 13y ago
This looks closer to Mathematica/Maple/MATLAB than a basic calculator, although still nowhere near the power of those. Of course 1/0 should be +Infinity, not ?... (Disclaimer: I have a Mathematica console always open on my desktop, and regularly use it for all kinds of calculations.)
- milhous 13y ago
  Bingo. If I'm in front of a computer, Mathematica. If not near one, then Wolfram|Alpha app/PCalc Lite on my iPad, else TI-83. But I've had my eyes on the HP Prime for a while. That'd be a huge jump from the 83!
- cycrutchfield 13y ago
  Why should 1/0 be +Infinity? Think of 1/x at the limit as x->0 from the left and from the right
  - chinpokomon 13y ago
    I still think the 1/0 problem can be solved if we step outside Euclidian geometry. It is undefined for the very reason you give. The Numberphile YouTube channel has an excellent video [1] discussing why x/0 is undefined and worth watching. [1] https://www.youtube.com/watch?v=BRRolKTlF6Q https://www.youtube.com/watch?v=BRRolKTlF6Q
  - mbq 13y ago
    With IEEE floats, 0 has a sign which can be used to denote the direction of the limit; if you try 1/(-0) in any program or language with sane numerics (i.e. not Excel or other dumb calculator emulators), it should give you -Infinity.
- Void_ 13y ago
  Why do you put that down as "disclaimer". This is why people make fun of us.
airtonix 13y ago
And now for the majority market share, the android version?
- avolcano 13y ago
  Just because an OS has a "majority market share" doesn't make it a suitable market. Elegant, minimal premium apps like Clear have done well on the iOS app store, but it's hard to imagine a $5 calculator app getting much interest on Android.
  - chinpokomon 13y ago
    Why is that hard to imagine? If the application were released for Android, I would have considered it. I've already purchased several Android calculators. There's no real basis for your claim, but I say this while I also realize I haven't provided sufficient evidence to support why Android would be a better platform. The reason I think a lot of applications like this fail on Android is that the developers first target iOS and then try to port it to Android without really designing for Android. The result is something lackluster that doesn't really work for Android devices.
    - corkill 13y ago
      Although you may personally have considered purchasing this calculator on Android. I think he was hinting at the fact that an IOS user is more likely on average to purchase an app and pay a premium for it, hence being more lucrative for developers even with less market share. "the App Store generated 2.3x more revenues than Google Play." http://www.theguardian.com/technology/2013/aug/01/android-apple-google-play-apps http://www.theguardian.com/technology/2013/aug/01/android-ap...
      - troymc 13y ago
        It's probably not a good idea to make a decision for a specific app based on the average behavior across all apps, unless your app is "average." A calculator app is an outlier; it is not an average app. It's also an outlier with real utility --- so it's something people are more likely to pay for.
zarify 13y ago
I basically stopped using "calculators" when Soulver and more recently Calca came out. Much easier to use and a lot more flexible. That said the graphing in this looks quite nice.
- Lazare 13y ago
  Wow, Calca is amazing. Thanks for the tip. :)
  - peterhajas 13y ago
    Calca is such a great calculator. I've encountered some issues where it refuses to recompute (systems of equations confuse it when you keep redefining variables), but I suppose that's not what it's for. I love being able to define real functions in it. The documentation is also all composed in Calca, which is helpful.
    - ketralnis 13y ago
      I've seen it be really awkward with whitespace, usually when I think it's not recalculating it's because of a stray or missing space somewhere that's keeping it from seeing that something is an equation (it tries to auto detect between equations and markdown). The common case for me is that I keep a very short-term personal ledger in it, just the stuff that hasn't hit the bank account yet, like this: chequing = (1,000 # current balance - 2 # coffee - 15 # groceries + 2 # Joe paid me back ) => 985 But messing up the spacing in any way, for instance like this: chequing = (1,000 # current balance - 2 # coffee - 15 # groceries + 20 # Joe paid me back ) => 985 (note one fewer space before the closing paren) and now no changes to the values inside the parens take effect on the total after the => (which for non-Calca-using spectators should always auto-update based on changes). I copy-pasted this out of Calca just now and you can see the the total is incorrect. Sometimes this messes up the syntax highlighting so that it's obvious, but usually it doesn't, and I'm left wondering why it's not updating.
- ketralnis 13y ago
  Calca is amazingly good for its simplicity. It's replaced my use of Excel for the cases that Excel was overkill. Well worth the $5
wsr 13y ago
As a Matlab enthusiast, this is probably the coolest thing I've seen in years. Good job guys, I have high hope for this in the future!
ra3 13y ago
Looks great. Just needs a new name. Tydlig?
- wingerlang 13y ago
  It means clear/apparent/obvious in Swedish.
  - eknkc 13y ago
    I was just thinking about IKEA after seeing the name.
- ethor 13y ago
  It is Swedish for apparent (clear).
- sorenvrist 13y ago
  (Edit: it is swedish and...) Almost danish/norwegian: Tydelig == Apparent/Clear
  - dwc 13y ago
    Litt mer øst...
  - jsilence 13y ago
    In German the slang word tüddelig means fiddly or flimsy.
- josteink 13y ago
  As opposed to the weekly hipster-named gxstmo.io or whatever similar comes along? Tydlig at least means something in a real language ;)
anilshanbhag 13y ago
I would just a ipython console Gone is the age of calculator
csmuk 13y ago
No RPN. Neckbeard status confirmed. Calculators are still an unsolved problem for me on glass devices to the point I still religiously carry around an HP50G even though its 6x the size of my phone. Also from some bad experiences, it appears that some "app" calculators are also seriously badly implemented. Even basic trig ops can return stupid values at extremes which makes them untrustworthy. Plus none are reasonably programmable. My use cases are base conversions, simple CAS stuff, basic engineering calculations, unit conversions, financial (TVM etc) and generic math. I also canned a lot of knowledge in RPL programs over the years from fuel calculations to diagnostic tools and dice rollers etc. Please can someone solve all these problems (without doing half arsed HP calc emulation).
- chinpokomon 13y ago
  I just replaced the batteries in my 48GX. I think in stacks and RPN is a better system for how I think. I have 48GX emulators for my phone and still use them over more modern calculator apps. That being said, I appreciate the design considerations they've applied to this. I wish they'd make an Android version, because I might have been interested in trying this out.
  - ghaff 13y ago
    It's funny how, for some things, you tend to be more comfortable with whatever you're used to even if nothing newer is objectively better. I used an HP-55 for years and then an HP-41. The newer HP graphic calculators never did a lot for me and I still use an HP-41 emulator on my iPhone for most of my calculating--though I'll pull out a physical HP calculator is I need to do a lot of calculating.
- melloclello 13y ago
  I'm working on an RPN calculator (with some pretty sweet gestural functionality) which solves approximately half of those problems. Wait, no, more like a quarter. Welp. It does return the correct value for sin(π) though (you gotta call __sinpi(x / M_PI) if you don't want to return -8.74e-8 or some ridiculous value).
karlshea 13y ago
Seems sort of like a slicker Soulver, I'm going to give it a shot.
pranayairan 13y ago
beautiful
notpg 13y ago
For the iphone and ipad? You mean for direct interface devices? (is there any reason this couldn't be applied to non idevices?)
- ketralnis 13y ago
  Because it's written for UIKit for iOS, presumably in Objective C?
lajospajtek 13y ago
Good to see that Bret Victor's ideas outlined in "Inventing on Principle" start taking some foothold.
- hisham_hm 13y ago
  Impressed to see only one comment, with no discussions, mentioning Bret Victor. His influence is clear on this work.
edoloughlin 13y ago
Tydlig supports external Bluetooth keyboards or numpads for really quick entry It's been a while since i did any ios development and this was never a requirement for me. Can someone explain why an external keyboard is something that had to be explicitly supported at an individual app level? Surely this should be an OS-level thing?
- interpol_p 13y ago
  It's not an explicit requirement, but you definitely need to test your app with an external keyboard to polish the experience. Here's a couple of situations that can get you when supporting an external Bluetooth keyboard: - Input accessory view. If you use an input accessory view (bar that sits atop the regular software keyboard), then connecting an external keyboard will cause the software keyboard to hide but keep the accessory view on screen. This is great — but if you had any controls underneath the keyboard (especially on iPad) that required the user to dismiss the keyboard to get to them, then you have to build a way for them to 'dismiss' the keyboard when using an external keyboard. - Custom keyboard. You might build a custom keyboard for your app. Connecting an external one will not show your custom keyboard. You'll need to ensure that functionality is still provided when an external keyboard is connected. There are a few other things like making sure your keyboard view resizing code is robust enough to handle all the possible state transitions ("no input -> software input -> bluetooth input", or "no input -> bluetooth input -> software input", and so on). If you're just using a standard text view you probably don't need to do anything special. But in this case Tydlig seems to do a lot of special stuff and probably required a bit of extra work to get Bluetooth keyboards running without issue.
cormullion 13y ago
I love this app, and it's interesting to see the innovation in this familiar space. Oovium for iPad is a great example of fresh thinking. And coming soon, apparently, is the Wolfram Calculator for iPad, featuring user-programmable functions: http://mvid.wolfram.com/mobile/dannewman_teachconceptsnotkeystrokes_archive.mp4 http://mvid.wolfram.com/mobile/dannewman_teachconceptsnotkey...
- gcanyon 13y ago
  That interface is a bag of hurt, but it looks powerful.
nitinupparpelli 13y ago
Apple products are awesome.. .. i am a big fan of apple and am very curious to know what they have got next in their stores
diziet 13y ago
This is great, though there are 15,230 calculator apps on iPhone alone. Tydlig ranks as #443 in the US for 'calculator', quite a tough fight!
oliwary 13y ago
I love it! Great design and should be very flexible to create simple functions through linked numbers. Is it really a good idea to allow 96 + 15% though (at 0:45)? Might cause some problems for people learning maths, as it won't work on normal calculators and doesn't really make it obvious what percentages actually are.
- HCIdivision17 13y ago
  The New Old Thing has an article on this topic [1]. Personally, I avoid ever using the percent button simply because I can never remember exactly how it will behave. [1] http://blogs.msdn.com/b/oldnewthing/archive/2008/01/10/7047497.aspx http://blogs.msdn.com/b/oldnewthing/archive/2008/01/10/70474...
jimmytidey 13y ago
Can we have something other than jingly guitar music for tech videos?
pfisch 13y ago
This looks much worse than symcalc. SymCalc has pretty much all the functionality of a TI-89 including solving calculus and algebraic equations. Tydlig looks like it has a nice ui but it doesn't even seem to support variables....
- jamesjguthrie 13y ago
  Thanks for the recommendation for SymCalc, I've just downloaded it. I had been using TouchCalc and GraphCalc but this is much better!
stormbrew 13y ago
This really seems much more like a freeform spreadsheet than a calculator to me. Which is also a cool idea, obviously, but I find it interesting no one else has made the same observation.
fpp 13y ago
On Android you have a choice of TI Calculator emulations see https://play.google.com/store/apps/details?id=com.Bisha.TI89Emu https://play.google.com/store/apps/details?id=com.Bisha.TI89... or http://www.androidpolice.com/2012/02/15/nostalgia-ti-89-calculator-emulator-finally-comes-to-android-download-it-while-you-still-can/ http://www.androidpolice.com/2012/02/15/nostalgia-ti-89-calc...
dirtyaura 13y ago
Great work. A few thoughts from the initial experience: I like the linked numbers design. As it reminded me of Bret Victor's work, I was expecting scrubbing to work directly with numbers, which caused occasionally a bit of havoc, but I think you did a right choice of putting linking as the main action - touch design is hard. The free-form infinite layout gives a mindmap vibe: it's potentially great when you are trying to understand pieces of a problem that you need. The downside is that the canvas becomes a bit of mess quickly. The other alternative could be a Mathematica style, free-form document, with more restricted flow of equations (and text). Because the organization becomes a bit of problem, undo is a must and solves a bunch of other problems. I'd implement area selection of equations (initiate with long tap?) to quickly move things around. Y-axis could auto adjust by default or quick slider scrubbing should work directly for axis max-min values. You probably want a simple document model as this is something between calculator and full featured computation software. Maybe just save every canvas when user clears/starts new one All in all, great work!
smikhanov 13y ago
Great to see more people attacking the underserved math app segment on the iOS. I'm the author of Scalar (http://scalarapp.com http://scalarapp.com), another calculator replacement for iPhone / iPad. Just tested both versions of Tydlig very heavily, looks like the author ran into lots of the similar math/UI problems as I did when I was working on my app. :) Some approaches he has chosen look similar, some are unique. Great work, good luck!
- rooster8 13y ago
  I'd love to hear you highlight a few of the unexpected challenges.
  - smikhanov 13y ago
    For example: 1. When someone enters "1 / 3" how many decimal places you display in the result? My approach: use MAX(4, MAX(decimal_places(entered_values))). His approach: use 3 everywhere. - Bonus 1: how many decimal places you display when someone enters "sin(3.14)"? What about "sin(1 / 3)"? My approach: use as much space you have on the screen. - Bonus 2: how do decimal places propagate when you're using refs? 2. What to do when someone taps "=" on the expression where we already have a result? Chinese $2 hardware calculator approach: redo the last operation. My approach: do nothing. Tydlig's approach: insert last result as a ref. 3. What to do when someone enters huge numbers? My approach: trim them to the width of the screen, clearly displaying that, but keep the full figure when doing copy/paste or export to text. His approach: start using E-notation somewhere around 16th figure. 4. In an app like this there's a temptation to stop using cursor because calculators don't have it and you want to be backwards compatible with them. When you create a ref, how to make sure the destination of the ref is at the right position in the expression without introducing a cursor? I.e. how to make sure you're not getting "2 + 3 [ref] + 12" (you need an operator before "[ref]")? My approach: use a semi-rigid table, where operators are separated from operands. Tydlig's approach: use a little cursor, a part of the app I don't like, because your finger normally would block the cursor. I can go on and on. Math-related stuff is hard.
    - 13y ago
daturkel 13y ago
Just a heads up, the inverse hyperbolic trig functions are arsinh, arcosh, and artanh. That's "ar" and not "arc" which stands for area.
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zschallz 13y ago
Very cool. Unfortunately, I think the price point is a bit too high (at least for me).
- pazimzadeh 13y ago
  $5 for a calculator with updateable functionality?
snambi 13y ago
excellent new idea.
ricardobeat 13y ago
If you're mainly interested in having all calculation steps visible and 'linked', there is also a great app called Digits (https://itunes.apple.com/us/app/digits-calculator-for-ipad/id364500115?mt=8 https://itunes.apple.com/us/app/digits-calculator-for-ipad/i...) which is at $0.99 right now.
acqq 13y ago
Which number system does it use? 8-byte doubles or its own library? What are the ranges? On which libraries is it based? Does it have complex numbers?
protomyth 13y ago
This looks very nice, and I'll probably buy it and Scalar this week, but it did get me to wondering. It would be interesting to see how an APL app would fair these days.
kangax 13y ago
It would be fun to build this as a webapp in JS + canvas/SVG.
jweir 13y ago
So I bought it Here are my thoughts as I use it (I will add to this comment. Hopefully the kids won't wake up soon.) Wish there was an UNDO. I just moved a number and didn't want too. Shake to UNDO? Pinch to zoom in and out. I'm using this on an iPhone. Can I save a canvas? It doesn't look like, but maybe I'm missing it.
sifarat 13y ago
Handsdown it has pretty good ui. But i regret buying it, because i can't calculate % seriously why isn't on the front. I have to press folder button to find it. additionally, I am baffled why do i have to press = to find end result, it should automatically calculate as i enter figure just like my $3 citizen calculator does.
bukka 13y ago
I was actually working on something really similar. (http://i.imgur.com/w4F8ms4.gif http://i.imgur.com/w4F8ms4.gif) It really is true that at any moment there is probably 4 other teams working on a similar idea as you are. Well I will not give up. Good luck to you too!
- melloclello 13y ago
  Dope interface, I would use that
songgao 13y ago
Nice work! Would be nice to have more tips on graphing. I spent 10 minutes and still can't figure out how to do graphs. The video on website is pretty helpful though.
- songgao 13y ago
  Never mind... The video is in intro guide!

411 points by Istof 13y ago

This looks great, for some uses, but I know myself (and a lot of my coworkers) would much prefer a beautiful iPhone calculator that behaves more like a 10-key/adding machine than an iPython notebook.

mwc 13y ago

The linked numbers are brilliant. Lacking the "in my head" math skills I should probably have, I regularly whip out Excel to solve the kind of use cases you can imagine from the linked numbers in the video.

jckt 13y ago

Graphing functionality on a phone reminds me of an old TI calculator. I really don't know why recent OSes (be it on PC, smartphone, tablet) always came with such feeble calculators. It's not like TI calculators are difficult to use. Sure if all you want is add/min/mul/div functionality the TI is essentially a traditional calculator, and then behind that you've got all these nifty graphing utilities. It's not like a graphing calculator app is going to be that difficult to program, or going to be large in size. But no, in 2013, vanilla OS installations are stuck with a calculator app that has less features than that of a computer a few million times less powerful. (Now I feel bad; bitching and complaining is against the Open Source Spirit). Edit: I do recall that OSX comes with something similar, except that not many people actually know of it (as far as I can tell, from my friends with OSX).

Void_ 13y ago
Bitching and complaining is good for products, makes them better. Don't know much about OSS spirit, but doesn't their work need any improvement??
- jckt 13y ago
  By OSS spirit I meant that it's better to get coding than start complaining. But I see your point -- indeed we should do both, and plenty of it.
shurcooL 13y ago
On that note, iPad doesn't even have the iPhone Calculator app, and it's _impossible_ to get it (without hacking) because it's a built-in app; one you cannot remove nor acquire from the App Store. It's also missing Compass, Voice Memo and Passbook apps. Edit: Weather app too.
- frik 13y ago
  yes weird, plus the weather app is missing too. What's the reasoning behind the decision? Was it Steve Jobs who decided that?
  - shurcooL 13y ago
    They just haven't created the full size iPad versions for them at this time. iOS 6/7 added some previously iPhone-only built-in apps.
  - cmelbye 13y ago
    I've always had a feeling that it's to differentiate iPad from iPhone. If they had the exact same apps, right down to a scaled up Calculator with gigantic buttons on the 10" display, it might make it less likely for consumers to think of iPad as a separate concept from iPhone. Calculator and Weather wouldn't really translate that well to a huge screen, anyways. And, of course, there are several great third-party apps to fill the void if you need them.
- superuser2 13y ago
  Missing compass because the WiFi version does not contain a GPS or magnetic compass.
  - shurcooL 13y ago
    There is a cellular version of the iPad too.
tolmasky 13y ago
Just a musing: perhaps its considered not as valuable an investment to program since a (the?) primary market is students, and students are probably not allowed to use phones on tests for obvious reasons (internet connectivity, texting questions to each other, overall distraction). However, TI's are state approved or whatever.
- fophillips 13y ago
  Never been allowed to use a TI for exams in the UK. I've only ever been allowed to use a Casio.
  - cmelbye 13y ago
    It's incredibly common for TI calculators to be allowed on exams in the United States. Several standardized tests specifically allow only TI calculators, along with a few others. I think GP's comment makes a lot of sense. Most students just aren't going to put the effort into learning how to use another graphing calculator program if they can't even use it in class.
  - asselinpaul 13y ago
    I am currently in Year 13 in London. You are definitely allowed TI in the mathematics exams (A-Levels). TI-89 is one of the only that is banned because of its CAS. Friends in the French system are allowed the TI 89 though.
    - burriko 13y ago
      Yep, I did Maths A-level in the UK back in the 90s, and a TI graphing calculator was basically a requirement for the exams.
      - fophillips 13y ago
        Interesting, I wasn't allowed to use one in A-Levels or university exams.
    - 13y ago
fredsted 13y ago
Yep, Grapher is a nice app with an interesting history: http://en.wikipedia.org/wiki/Grapher http://en.wikipedia.org/wiki/Grapher
- Someone 13y ago
  Does Grapher share any source with Graphing Calculator? I guess it might, given that Apple shipped Graphing Calculator with Mac OS before, and given Graphing Calculator's interesting early history (http://www.pacifict.com/Story/ http://www.pacifict.com/Story/) (I wonder how Apple negotiated that deal originally. I guess some lawyers spent quite some time arguing whose intellectual property it originally was. The programmers weren't paid by Apple, but worked at Infinite Loop)
Someone 13y ago
"It's not like a graphing calculator app is going to be that difficult to program" It is surprisingly hard to get something that produces reliable plots. It starts with getting something as simple as sin(1/x) or x/(x^2 + 5x + 1) to plot reasonably well, and gets harder from there soon (edit: if you want to complicate things, pick a function that is only defined on some numbers, such as sqrt(x^2 * sin(x^3 - x). Adding a pair of || around subexpressions also complicates things) For example, at https://www.desmos.com/calculator https://www.desmos.com/calculator (one of the top results from a google search) zooming in on sin(1/x) shows a plot that sometimes doesn't go up to 1.0 for values of x close to zero. Its plot is decent, but deceiving. And you will have to do those well, as the target audience of students encounters such functions every day. And the Mac OS X one is Grapher (http://en.wikipedia.org/wiki/Grapher http://en.wikipedia.org/wiki/Grapher)
bane 13y ago
It's depressing to me that the closest I can get to the TI-92+ I had in college is to emulate a TI-92+ on my computer or Android devices (actually on a tablet it's not too bad). My other options (Octave, Matlab, etc.) are way too heavy for what I want to do and require too much time to learn. They don't have that sort of pickup-and-use feature my old calculators used to have. I think it's the presence of most of the buttons I'm ever going to be interested in on the keyboard rather than having to figure out how to type something that means the same as an integral or some such. The discoverability of those buttons beats most modern software hands down. I also suspect that writing simple to use general purpose solvers and simplifiers for the things the TI calcs do (the CAS) is likely very hard. I remember putting even pretty complex physics equations with all sorts of trig functions and exponents and integrals and such in during college and it handled most of them without trouble and pretty printed the result.
- csmuk 13y ago
  Ha I had a TI92 (not plus) a number of years ago. Weighed a ton - you could kill someone with it. Sold it and got an HP48GX after I discovered that you couldn't get the plus module for it in the UK for a reasonable price. Never looked back.
- cstejerean 13y ago
  I miss my TI-92+ as well. It feels like an iPad has enough screen real estate to be able to simulate the same experience, and I was surprised that nobody has done it yet. Edit: looks like there are some good options for Android that actually emulate TI calculators, and apparently TI has Nspire for the iPad.
robterrell 13y ago
On OS X it's Graphing Calculator. See the amazing story behind it: http://www.pacifict.com/Story/ http://www.pacifict.com/Story/
- axman6 13y ago
  I was just going to write this comment myself before checking to see if I'd been beaten. It's definitely one of the great stories of computer history.

userbinator 13y ago

This looks closer to Mathematica/Maple/MATLAB than a basic calculator, although still nowhere near the power of those. Of course 1/0 should be +Infinity, not ?... (Disclaimer: I have a Mathematica console always open on my desktop, and regularly use it for all kinds of calculations.)

milhous 13y ago
Bingo. If I'm in front of a computer, Mathematica. If not near one, then Wolfram|Alpha app/PCalc Lite on my iPad, else TI-83. But I've had my eyes on the HP Prime for a while. That'd be a huge jump from the 83!
cycrutchfield 13y ago
Why should 1/0 be +Infinity? Think of 1/x at the limit as x->0 from the left and from the right
- chinpokomon 13y ago
  I still think the 1/0 problem can be solved if we step outside Euclidian geometry. It is undefined for the very reason you give. The Numberphile YouTube channel has an excellent video [1] discussing why x/0 is undefined and worth watching. [1] https://www.youtube.com/watch?v=BRRolKTlF6Q https://www.youtube.com/watch?v=BRRolKTlF6Q
- mbq 13y ago
  With IEEE floats, 0 has a sign which can be used to denote the direction of the limit; if you try 1/(-0) in any program or language with sane numerics (i.e. not Excel or other dumb calculator emulators), it should give you -Infinity.
Void_ 13y ago
Why do you put that down as "disclaimer". This is why people make fun of us.

airtonix 13y ago

And now for the majority market share, the android version?

avolcano 13y ago
Just because an OS has a "majority market share" doesn't make it a suitable market. Elegant, minimal premium apps like Clear have done well on the iOS app store, but it's hard to imagine a $5 calculator app getting much interest on Android.
- chinpokomon 13y ago
  Why is that hard to imagine? If the application were released for Android, I would have considered it. I've already purchased several Android calculators. There's no real basis for your claim, but I say this while I also realize I haven't provided sufficient evidence to support why Android would be a better platform. The reason I think a lot of applications like this fail on Android is that the developers first target iOS and then try to port it to Android without really designing for Android. The result is something lackluster that doesn't really work for Android devices.
  - corkill 13y ago
    Although you may personally have considered purchasing this calculator on Android. I think he was hinting at the fact that an IOS user is more likely on average to purchase an app and pay a premium for it, hence being more lucrative for developers even with less market share. "the App Store generated 2.3x more revenues than Google Play." http://www.theguardian.com/technology/2013/aug/01/android-apple-google-play-apps http://www.theguardian.com/technology/2013/aug/01/android-ap...
    - troymc 13y ago
      It's probably not a good idea to make a decision for a specific app based on the average behavior across all apps, unless your app is "average." A calculator app is an outlier; it is not an average app. It's also an outlier with real utility --- so it's something people are more likely to pay for.

zarify 13y ago

I basically stopped using "calculators" when Soulver and more recently Calca came out. Much easier to use and a lot more flexible. That said the graphing in this looks quite nice.

Lazare 13y ago
Wow, Calca is amazing. Thanks for the tip. :)
- peterhajas 13y ago
  Calca is such a great calculator. I've encountered some issues where it refuses to recompute (systems of equations confuse it when you keep redefining variables), but I suppose that's not what it's for. I love being able to define real functions in it. The documentation is also all composed in Calca, which is helpful.
  - ketralnis 13y ago
    I've seen it be really awkward with whitespace, usually when I think it's not recalculating it's because of a stray or missing space somewhere that's keeping it from seeing that something is an equation (it tries to auto detect between equations and markdown). The common case for me is that I keep a very short-term personal ledger in it, just the stuff that hasn't hit the bank account yet, like this: chequing = (1,000 # current balance - 2 # coffee - 15 # groceries + 2 # Joe paid me back ) => 985 But messing up the spacing in any way, for instance like this: chequing = (1,000 # current balance - 2 # coffee - 15 # groceries + 20 # Joe paid me back ) => 985 (note one fewer space before the closing paren) and now no changes to the values inside the parens take effect on the total after the => (which for non-Calca-using spectators should always auto-update based on changes). I copy-pasted this out of Calca just now and you can see the the total is incorrect. Sometimes this messes up the syntax highlighting so that it's obvious, but usually it doesn't, and I'm left wondering why it's not updating.
ketralnis 13y ago
Calca is amazingly good for its simplicity. It's replaced my use of Excel for the cases that Excel was overkill. Well worth the $5

wsr 13y ago

As a Matlab enthusiast, this is probably the coolest thing I've seen in years. Good job guys, I have high hope for this in the future!

ra3 13y ago

Looks great. Just needs a new name. Tydlig?

wingerlang 13y ago
It means clear/apparent/obvious in Swedish.
- eknkc 13y ago
  I was just thinking about IKEA after seeing the name.
ethor 13y ago
It is Swedish for apparent (clear).
sorenvrist 13y ago
(Edit: it is swedish and...) Almost danish/norwegian: Tydelig == Apparent/Clear
- dwc 13y ago
  Litt mer øst...
- jsilence 13y ago
  In German the slang word tüddelig means fiddly or flimsy.
josteink 13y ago
As opposed to the weekly hipster-named gxstmo.io or whatever similar comes along? Tydlig at least means something in a real language ;)

anilshanbhag 13y ago

I would just a ipython console Gone is the age of calculator

csmuk 13y ago

No RPN. Neckbeard status confirmed. Calculators are still an unsolved problem for me on glass devices to the point I still religiously carry around an HP50G even though its 6x the size of my phone. Also from some bad experiences, it appears that some "app" calculators are also seriously badly implemented. Even basic trig ops can return stupid values at extremes which makes them untrustworthy. Plus none are reasonably programmable. My use cases are base conversions, simple CAS stuff, basic engineering calculations, unit conversions, financial (TVM etc) and generic math. I also canned a lot of knowledge in RPL programs over the years from fuel calculations to diagnostic tools and dice rollers etc. Please can someone solve all these problems (without doing half arsed HP calc emulation).

chinpokomon 13y ago
I just replaced the batteries in my 48GX. I think in stacks and RPN is a better system for how I think. I have 48GX emulators for my phone and still use them over more modern calculator apps. That being said, I appreciate the design considerations they've applied to this. I wish they'd make an Android version, because I might have been interested in trying this out.
- ghaff 13y ago
  It's funny how, for some things, you tend to be more comfortable with whatever you're used to even if nothing newer is objectively better. I used an HP-55 for years and then an HP-41. The newer HP graphic calculators never did a lot for me and I still use an HP-41 emulator on my iPhone for most of my calculating--though I'll pull out a physical HP calculator is I need to do a lot of calculating.
melloclello 13y ago
I'm working on an RPN calculator (with some pretty sweet gestural functionality) which solves approximately half of those problems. Wait, no, more like a quarter. Welp. It does return the correct value for sin(π) though (you gotta call __sinpi(x / M_PI) if you don't want to return -8.74e-8 or some ridiculous value).

karlshea 13y ago

Seems sort of like a slicker Soulver, I'm going to give it a shot.

pranayairan 13y ago

beautiful

notpg 13y ago

For the iphone and ipad? You mean for direct interface devices? (is there any reason this couldn't be applied to non idevices?)

ketralnis 13y ago
Because it's written for UIKit for iOS, presumably in Objective C?

lajospajtek 13y ago

Good to see that Bret Victor's ideas outlined in "Inventing on Principle" start taking some foothold.

hisham_hm 13y ago
Impressed to see only one comment, with no discussions, mentioning Bret Victor. His influence is clear on this work.

edoloughlin 13y ago

Tydlig supports external Bluetooth keyboards or numpads for really quick entry It's been a while since i did any ios development and this was never a requirement for me. Can someone explain why an external keyboard is something that had to be explicitly supported at an individual app level? Surely this should be an OS-level thing?

interpol_p 13y ago
It's not an explicit requirement, but you definitely need to test your app with an external keyboard to polish the experience. Here's a couple of situations that can get you when supporting an external Bluetooth keyboard: - Input accessory view. If you use an input accessory view (bar that sits atop the regular software keyboard), then connecting an external keyboard will cause the software keyboard to hide but keep the accessory view on screen. This is great — but if you had any controls underneath the keyboard (especially on iPad) that required the user to dismiss the keyboard to get to them, then you have to build a way for them to 'dismiss' the keyboard when using an external keyboard. - Custom keyboard. You might build a custom keyboard for your app. Connecting an external one will not show your custom keyboard. You'll need to ensure that functionality is still provided when an external keyboard is connected. There are a few other things like making sure your keyboard view resizing code is robust enough to handle all the possible state transitions ("no input -> software input -> bluetooth input", or "no input -> bluetooth input -> software input", and so on). If you're just using a standard text view you probably don't need to do anything special. But in this case Tydlig seems to do a lot of special stuff and probably required a bit of extra work to get Bluetooth keyboards running without issue.

cormullion 13y ago

I love this app, and it's interesting to see the innovation in this familiar space. Oovium for iPad is a great example of fresh thinking. And coming soon, apparently, is the Wolfram Calculator for iPad, featuring user-programmable functions: http://mvid.wolfram.com/mobile/dannewman_teachconceptsnotkeystrokes_archive.mp4 http://mvid.wolfram.com/mobile/dannewman_teachconceptsnotkey...

gcanyon 13y ago
That interface is a bag of hurt, but it looks powerful.

nitinupparpelli 13y ago

Apple products are awesome.. .. i am a big fan of apple and am very curious to know what they have got next in their stores

diziet 13y ago

This is great, though there are 15,230 calculator apps on iPhone alone. Tydlig ranks as #443 in the US for 'calculator', quite a tough fight!

oliwary 13y ago

I love it! Great design and should be very flexible to create simple functions through linked numbers. Is it really a good idea to allow 96 + 15% though (at 0:45)? Might cause some problems for people learning maths, as it won't work on normal calculators and doesn't really make it obvious what percentages actually are.

HCIdivision17 13y ago
The New Old Thing has an article on this topic [1]. Personally, I avoid ever using the percent button simply because I can never remember exactly how it will behave. [1] http://blogs.msdn.com/b/oldnewthing/archive/2008/01/10/7047497.aspx http://blogs.msdn.com/b/oldnewthing/archive/2008/01/10/70474...

jimmytidey 13y ago

Can we have something other than jingly guitar music for tech videos?

pfisch 13y ago

This looks much worse than symcalc. SymCalc has pretty much all the functionality of a TI-89 including solving calculus and algebraic equations. Tydlig looks like it has a nice ui but it doesn't even seem to support variables....

jamesjguthrie 13y ago
Thanks for the recommendation for SymCalc, I've just downloaded it. I had been using TouchCalc and GraphCalc but this is much better!

stormbrew 13y ago

This really seems much more like a freeform spreadsheet than a calculator to me. Which is also a cool idea, obviously, but I find it interesting no one else has made the same observation.

fpp 13y ago

On Android you have a choice of TI Calculator emulations see https://play.google.com/store/apps/details?id=com.Bisha.TI89Emu https://play.google.com/store/apps/details?id=com.Bisha.TI89... or http://www.androidpolice.com/2012/02/15/nostalgia-ti-89-calculator-emulator-finally-comes-to-android-download-it-while-you-still-can/ http://www.androidpolice.com/2012/02/15/nostalgia-ti-89-calc...

dirtyaura 13y ago

Great work. A few thoughts from the initial experience: I like the linked numbers design. As it reminded me of Bret Victor's work, I was expecting scrubbing to work directly with numbers, which caused occasionally a bit of havoc, but I think you did a right choice of putting linking as the main action - touch design is hard. The free-form infinite layout gives a mindmap vibe: it's potentially great when you are trying to understand pieces of a problem that you need. The downside is that the canvas becomes a bit of mess quickly. The other alternative could be a Mathematica style, free-form document, with more restricted flow of equations (and text). Because the organization becomes a bit of problem, undo is a must and solves a bunch of other problems. I'd implement area selection of equations (initiate with long tap?) to quickly move things around. Y-axis could auto adjust by default or quick slider scrubbing should work directly for axis max-min values. You probably want a simple document model as this is something between calculator and full featured computation software. Maybe just save every canvas when user clears/starts new one All in all, great work!

smikhanov 13y ago

Great to see more people attacking the underserved math app segment on the iOS. I'm the author of Scalar (http://scalarapp.com http://scalarapp.com), another calculator replacement for iPhone / iPad. Just tested both versions of Tydlig very heavily, looks like the author ran into lots of the similar math/UI problems as I did when I was working on my app. :) Some approaches he has chosen look similar, some are unique. Great work, good luck!

rooster8 13y ago
I'd love to hear you highlight a few of the unexpected challenges.
- smikhanov 13y ago
  For example: 1. When someone enters "1 / 3" how many decimal places you display in the result? My approach: use MAX(4, MAX(decimal_places(entered_values))). His approach: use 3 everywhere. - Bonus 1: how many decimal places you display when someone enters "sin(3.14)"? What about "sin(1 / 3)"? My approach: use as much space you have on the screen. - Bonus 2: how do decimal places propagate when you're using refs? 2. What to do when someone taps "=" on the expression where we already have a result? Chinese $2 hardware calculator approach: redo the last operation. My approach: do nothing. Tydlig's approach: insert last result as a ref. 3. What to do when someone enters huge numbers? My approach: trim them to the width of the screen, clearly displaying that, but keep the full figure when doing copy/paste or export to text. His approach: start using E-notation somewhere around 16th figure. 4. In an app like this there's a temptation to stop using cursor because calculators don't have it and you want to be backwards compatible with them. When you create a ref, how to make sure the destination of the ref is at the right position in the expression without introducing a cursor? I.e. how to make sure you're not getting "2 + 3 [ref] + 12" (you need an operator before "[ref]")? My approach: use a semi-rigid table, where operators are separated from operands. Tydlig's approach: use a little cursor, a part of the app I don't like, because your finger normally would block the cursor. I can go on and on. Math-related stuff is hard.
  - 13y ago

daturkel 13y ago

Just a heads up, the inverse hyperbolic trig functions are arsinh, arcosh, and artanh. That's "ar" and not "arc" which stands for area.

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- deleted 13y ago
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zschallz 13y ago

Very cool. Unfortunately, I think the price point is a bit too high (at least for me).

pazimzadeh 13y ago
$5 for a calculator with updateable functionality?

snambi 13y ago

excellent new idea.

ricardobeat 13y ago

If you're mainly interested in having all calculation steps visible and 'linked', there is also a great app called Digits (https://itunes.apple.com/us/app/digits-calculator-for-ipad/id364500115?mt=8 https://itunes.apple.com/us/app/digits-calculator-for-ipad/i...) which is at $0.99 right now.

acqq 13y ago

Which number system does it use? 8-byte doubles or its own library? What are the ranges? On which libraries is it based? Does it have complex numbers?

protomyth 13y ago

This looks very nice, and I'll probably buy it and Scalar this week, but it did get me to wondering. It would be interesting to see how an APL app would fair these days.

kangax 13y ago

It would be fun to build this as a webapp in JS + canvas/SVG.

jweir 13y ago

So I bought it Here are my thoughts as I use it (I will add to this comment. Hopefully the kids won't wake up soon.) Wish there was an UNDO. I just moved a number and didn't want too. Shake to UNDO? Pinch to zoom in and out. I'm using this on an iPhone. Can I save a canvas? It doesn't look like, but maybe I'm missing it.

sifarat 13y ago

Handsdown it has pretty good ui. But i regret buying it, because i can't calculate % seriously why isn't on the front. I have to press folder button to find it. additionally, I am baffled why do i have to press = to find end result, it should automatically calculate as i enter figure just like my $3 citizen calculator does.

bukka 13y ago

I was actually working on something really similar. (http://i.imgur.com/w4F8ms4.gif http://i.imgur.com/w4F8ms4.gif) It really is true that at any moment there is probably 4 other teams working on a similar idea as you are. Well I will not give up. Good luck to you too!

melloclello 13y ago
Dope interface, I would use that

songgao 13y ago

Nice work! Would be nice to have more tips on graphing. I spent 10 minutes and still can't figure out how to do graphs. The video on website is pretty helpful though.

songgao 13y ago
Never mind... The video is in intro guide!