I've used so many other apps that assume you already know hiragana and I've spent so much time trying to just remember all of it with Quizlet. Not fun. This app seems to analyze how you answer and it picks good spots to throw in the characters you consistently miss so that you can learn from your failures. I came in knowing maybe 20% of hiragana and within half an hour I memorized all of it. Really nice job at matching the progression of difficulty to my progression of learning. It never felt difficult or frustrating, I would just miss some of the characters when I'd first see them, and the next time they'd come around, I'd usually remember them. Seriously, really good job with analyzing how I learn.

Edit: after the last update the app does not work at all. The developer changes the entire feel of the app every single time there's an update, adding/ removing kana, moving things, etc. The on screen keyboard works exceptionally poorly, I'm not sure why the developers would force us to use that instead of the keyboard on the phone that is actually responsive.