Fed up with the GPS-based loggers on old smartphones crashing when I stopped to take a pic, or a text came in, or some other random event - I cobbled together a few hardware bits to make my own ...
Then I got an iPhone 5s and while there is a Stava iOS app, it's data acquisition routines are woeful and they were completely uninterested when I reported it. My problem is with the massive GPS float that occurs when you stop riding for a couple of minutes to get your breath back (being a tubby bugger who took up biking after years sat behind a desk) - the auto-pause doesn't kick in and you end up with a GPS track that can have loads of extra miles on it. So I made a better loggerr, just for the sake of it ...