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My wife runs long distances with an iPhone AND a watch. My impression is that Forerunners have fallen out of favor. The GPS doesn't work all that well compared

by eli 12y ago

My wife runs long distances with an iPhone AND a watch. My impression is that Forerunners have fallen out of favor. The GPS doesn't work all that well compared to a phone (I'm guessing because it lacks the AGPS data a phone has access to). Plus if you're running a marathon you probably want some music to listen to, and it sure is nice to have a phone with you even though it's perhaps a bit heavy.

zimpenfish 12y ago
I've got 18 months of Moves data logged against corresponding tracks from my 910XT and the difference in consistency, accuracy, etc., is telling - the iPhone is frequently off by 10s (if not 100s) of metres and especially coming round the Millennium Dome is a joke - it has me jumping from the south to the north of the Thames every few hundred metres. Moves iPhone 5S - http://imgur.com/kjYf8Tj http://imgur.com/kjYf8Tj Garmin 910XT - http://imgur.com/jnXuaQC http://imgur.com/jnXuaQC
- cstuder 12y ago
  Did you disable WLAN on the iPhone during the run? That's what RunKeeper recommends, because the AGPS using WLAN-SSIDs lowers the accuracy of the tracking.
- bane 12y ago
  I bet your iphone is trying to use cell tower locations or wifi hotspots it's picking up around there and borking up the location. The area around there is kind of open and flat so I wouldn't be surprised if it's picking up location information from across the river.
  - zimpenfish 12y ago
    It does seem to be WiFi related. But if I have to remember to disable the WiFi whenever I want to do some GPS tracking - and if I forget, I basically get random garbage - that pushes it well into "no bloody use" for me.
    - aioprisan 12y ago
      That's a feature, not a bug ;)
      - theon144 12y ago
        Uh, no, I'm pretty sure that's a bug. Unless you literally want to consider inaccurate tracking a feature.
    - zak_mc_kracken 12y ago
      Surely there is an app for that? Android has plenty of apps that will automatically turn on/off your wifi based on various criteria, such as your location (I always turn it off as soon as I'm 50 yards away from home or from the office).
  - KJasper 12y ago
    Probably put these apps should compensate for the fact that humans can't run that fast nor that they can run over water.
  - terrence_giggy 12y ago
    I would bet it is the cycling of GPS that the app is doing. If GPS is just left on, a battery can get burned through in a couple hours (for one of the newer iPhones, much less an older one). Those wacky readings are some of the initial results after GPS is cycled back on. One might look for a higher power setting if you are doing an hour / half hour run and not concerned about keeping battery life up.
    - zimpenfish 12y ago
      Moves is on "battery saving" mode (which actually makes little difference - I get bugger all life out of my phone anyway) but that doesn't really explain why it's just around the O2 it has serious issues - that's only about 2-3km out of the whole 30km walk.
- eli 12y ago
  How long does the Garmin take to find you at the start of a run? I admittedly had an old model, but it was basically a dealbreaker with the forerunner. I was wandering around for 5-10 mins with my wrist in the air waiting to start.
  - zimpenfish 12y ago
    It's a lot better than the 310XT. I don't think it's taken more than a minute of standing still in the last few months. I do tend to start in pretty open sky'd places though.
  - schrodinger 12y ago
    Same here, I've got a Garmin watch and it's great once it finds satellites, but routinely takes well over 5 minutes to do so (in NYC). I've started using my iphone to track runs and bike rides instead, only using the Garmin for really long bike rides where I don't mind the wait and having my current speed on my wrist is worth the wait.
  - tspiteri 12y ago
    I used to have to wait for a fix as well. What works for me is that when I'm preparing for the run, I put the watch in a window for enough time to get a fix, which sometimes take a long time. Then when I go out to run later, it gets a fix pretty quickly.
  - orbitur 12y ago
    I use the 910XT in a very cloudy part of the world (which I'm assuming makes things worse). I've just integrated the startup time into my prep. Before I put my running stuff on, I turn on the watch and let it figure stuff out while I'm taping my nips, and if it's winter, gloves, tights, mentally bracing myself for the cold, etc.
  - rickyc091 12y ago
    The new models lock really quickly. I have a Garmin 620 and it locks within 30 seconds. Cloudy days might take a minute, but basically by the time I finish my warmup walk, it's locked on.
- eli 12y ago
  (Totally offtopic but running near the Whitehouse in DC is funny because they screw with GPS accuracy so you bounce all over the place)
  - schrodinger 12y ago
    How is that possible? GPS satellites are sending the same signal out to everyone, I don't see how they could possibly target a certain area.
    - a_c_s 12y ago
      I don't know how they do it, but if you drive by the Pentagon with a GPS unit you'll see it go crazy.
    - kweinber 12y ago
      Gps satellites all send slightly incorrect information... A separate radio signal correction is transmitted to correct it. That way, during wartime (or in high value target areas) the US can basically mess up enemy gps enabled weapons by broadcasting misleading satellite and correction data.
      - foldr 12y ago
        That doesn't answer the question of how they could make GPs inaccurate only in a specific area.
        sbalea 12y ago
        Low power GPS jammer at the Whitehouse, perhaps?
    - markild 12y ago
      The Economist[1] had a story about the London Stock Exchange getting jammed GPS-signal 10 minutes every day. I believe they are using something similar. [1]: http://www.economist.com/news/international/21582288-satellite-positioning-data-are-vitalbut-signal-surprisingly-easy-disrupt-out http://www.economist.com/news/international/21582288-satelli...
- megablast 12y ago
  I have found this with the phone, if I do a cold start. When I ride somewhere, start the tracking, the stop the tracking when I get to the run track, the iPhone is so much better at tracking me.
- syncsynchalt 12y ago
  Do you use a GPS app in your phone often? This almost looks like it was falling back to AGPS / Skyhook while the almanac was still downloading, which can take half an hour or so. Once the almanac is downloaded, the phone's GPS track should look much closer to the Garmin's. If this was a recurring problem then I don't know what to say, other than it doesn't match my experience with RunKeeper on an iPhone 4S.
  - zimpenfish 12y ago
    Well, I have Find My iPhone and 5 other motion trackers (Moves, Argus, Breeze, Human, Nike+) running 24/7 - it's a fair bet my GPS almanac is up to date since they should all be poking the M7 for updates.
PretendAway 12y ago
On some you can load AGPS data onto it for the next few days, but the bigger issue is that Garmin no longer uses SiRF chipsets, which are vastly superior when compared gen-for-gen vs. the generic stuff Garmin's using now. It's a shame, but the most accurate Forerunners are the older ones–same for Foretrex, etc.–which are often the ones with the shortest battery life.

by eli 12y ago

zimpenfish 12y ago

I've got 18 months of Moves data logged against corresponding tracks from my 910XT and the difference in consistency, accuracy, etc., is telling - the iPhone is frequently off by 10s (if not 100s) of metres and especially coming round the Millennium Dome is a joke - it has me jumping from the south to the north of the Thames every few hundred metres. Moves iPhone 5S - http://imgur.com/kjYf8Tj http://imgur.com/kjYf8Tj Garmin 910XT - http://imgur.com/jnXuaQC http://imgur.com/jnXuaQC

cstuder 12y ago
Did you disable WLAN on the iPhone during the run? That's what RunKeeper recommends, because the AGPS using WLAN-SSIDs lowers the accuracy of the tracking.
bane 12y ago
I bet your iphone is trying to use cell tower locations or wifi hotspots it's picking up around there and borking up the location. The area around there is kind of open and flat so I wouldn't be surprised if it's picking up location information from across the river.
- zimpenfish 12y ago
  It does seem to be WiFi related. But if I have to remember to disable the WiFi whenever I want to do some GPS tracking - and if I forget, I basically get random garbage - that pushes it well into "no bloody use" for me.
  - aioprisan 12y ago
    That's a feature, not a bug ;)
    - theon144 12y ago
      Uh, no, I'm pretty sure that's a bug. Unless you literally want to consider inaccurate tracking a feature.
  - zak_mc_kracken 12y ago
    Surely there is an app for that? Android has plenty of apps that will automatically turn on/off your wifi based on various criteria, such as your location (I always turn it off as soon as I'm 50 yards away from home or from the office).
- KJasper 12y ago
  Probably put these apps should compensate for the fact that humans can't run that fast nor that they can run over water.
- terrence_giggy 12y ago
  I would bet it is the cycling of GPS that the app is doing. If GPS is just left on, a battery can get burned through in a couple hours (for one of the newer iPhones, much less an older one). Those wacky readings are some of the initial results after GPS is cycled back on. One might look for a higher power setting if you are doing an hour / half hour run and not concerned about keeping battery life up.
  - zimpenfish 12y ago
    Moves is on "battery saving" mode (which actually makes little difference - I get bugger all life out of my phone anyway) but that doesn't really explain why it's just around the O2 it has serious issues - that's only about 2-3km out of the whole 30km walk.
eli 12y ago
How long does the Garmin take to find you at the start of a run? I admittedly had an old model, but it was basically a dealbreaker with the forerunner. I was wandering around for 5-10 mins with my wrist in the air waiting to start.
- zimpenfish 12y ago
  It's a lot better than the 310XT. I don't think it's taken more than a minute of standing still in the last few months. I do tend to start in pretty open sky'd places though.
- schrodinger 12y ago
  Same here, I've got a Garmin watch and it's great once it finds satellites, but routinely takes well over 5 minutes to do so (in NYC). I've started using my iphone to track runs and bike rides instead, only using the Garmin for really long bike rides where I don't mind the wait and having my current speed on my wrist is worth the wait.
- tspiteri 12y ago
  I used to have to wait for a fix as well. What works for me is that when I'm preparing for the run, I put the watch in a window for enough time to get a fix, which sometimes take a long time. Then when I go out to run later, it gets a fix pretty quickly.
- orbitur 12y ago
  I use the 910XT in a very cloudy part of the world (which I'm assuming makes things worse). I've just integrated the startup time into my prep. Before I put my running stuff on, I turn on the watch and let it figure stuff out while I'm taping my nips, and if it's winter, gloves, tights, mentally bracing myself for the cold, etc.
- rickyc091 12y ago
  The new models lock really quickly. I have a Garmin 620 and it locks within 30 seconds. Cloudy days might take a minute, but basically by the time I finish my warmup walk, it's locked on.
eli 12y ago
(Totally offtopic but running near the Whitehouse in DC is funny because they screw with GPS accuracy so you bounce all over the place)
- schrodinger 12y ago
  How is that possible? GPS satellites are sending the same signal out to everyone, I don't see how they could possibly target a certain area.
  - a_c_s 12y ago
    I don't know how they do it, but if you drive by the Pentagon with a GPS unit you'll see it go crazy.
  - kweinber 12y ago
    Gps satellites all send slightly incorrect information... A separate radio signal correction is transmitted to correct it. That way, during wartime (or in high value target areas) the US can basically mess up enemy gps enabled weapons by broadcasting misleading satellite and correction data.
    - foldr 12y ago
      That doesn't answer the question of how they could make GPs inaccurate only in a specific area.
      - sbalea 12y ago
        Low power GPS jammer at the Whitehouse, perhaps?
  - markild 12y ago
    The Economist[1] had a story about the London Stock Exchange getting jammed GPS-signal 10 minutes every day. I believe they are using something similar. [1]: http://www.economist.com/news/international/21582288-satellite-positioning-data-are-vitalbut-signal-surprisingly-easy-disrupt-out http://www.economist.com/news/international/21582288-satelli...
megablast 12y ago
I have found this with the phone, if I do a cold start. When I ride somewhere, start the tracking, the stop the tracking when I get to the run track, the iPhone is so much better at tracking me.
syncsynchalt 12y ago
Do you use a GPS app in your phone often? This almost looks like it was falling back to AGPS / Skyhook while the almanac was still downloading, which can take half an hour or so. Once the almanac is downloaded, the phone's GPS track should look much closer to the Garmin's. If this was a recurring problem then I don't know what to say, other than it doesn't match my experience with RunKeeper on an iPhone 4S.
- zimpenfish 12y ago
  Well, I have Find My iPhone and 5 other motion trackers (Moves, Argus, Breeze, Human, Nike+) running 24/7 - it's a fair bet my GPS almanac is up to date since they should all be poking the M7 for updates.

PretendAway 12y ago

On some you can load AGPS data onto it for the next few days, but the bigger issue is that Garmin no longer uses SiRF chipsets, which are vastly superior when compared gen-for-gen vs. the generic stuff Garmin's using now. It's a shame, but the most accurate Forerunners are the older ones–same for Foretrex, etc.–which are often the ones with the shortest battery life.