I've done this back in iPhone 3 era, and even made a few thousand dollars on the App Store when you could still make money there. You could improve this by adding a state machine to the algorithm. Basically, only count _repeat_ events, not single events. When you start walking, you start "provisionally" recording the peaks, which can be done fairly easily, but unless it's N peaks or more (IIRC 4 was a good number) wi…
> when you could still make money there. What has changed since? Speaking as someone who has never written apps before but have also wanted to in my spare time, what has changed from before?
Lots of competition, and you have to put in a _ton_ of work to get noticed. Most devs lose money on Apple's App Store I'm sure.