I'm curious to learn what drove you to do this, when it seems much more convenient and conducive for people to take advantage of services like several others ha

I'm curious to learn what drove you to do this, when it seems much more convenient and conducive for people to take advantage of services like several others have mentioned (Runkeeper, Runtastic, MyFitnessPal, even Nike+) that combine a web app with a mobile app. You get largely the same functionality on the web that you provide, plus social options (sharing workout plans & achievements, etc) and curated regimens put together by experts/professionals, _and_ you get the convenience of a mobile app with an ultra-simple touch UI to carry around in the gym for guiding you through each exercise & recording the results.