The better question is "Why do you want to build these things", because the answer to that question would help answer yours. Are you looking to make money? The

The better question is "Why do you want to build these things", because the answer to that question would help answer yours. Are you looking to make money? Then Chrome extensions probably aren't a great way to do it, given that they're distributed for free, and a dating app might be questionable, but an online video editor might be a good idea. Are you looking to make something you'd find useful for yourself? An in-browser video editor or gifplayer probably wouldn't be very useful for you, but the extensions could be very helpful for you. Are you looking to build up a portfolio? Then it doesn't matter which you build, all of the above projects probably would be okay portfolio pieces. I personally would not be interested in paying for any of the above, but as I'm trying to explain, that doesn't necessarily matter if you're not making it for money or you're not trying to cater to HN's demographic. Figure out what's guiding you and I'm sure you can filter at least half of the ideas off this list.