I'm really impressed with the Windows Phone community and their work on creating fantastic third party apps, some of which are even better than the originals. Because of this, most of the apps I need are on Windows Phone. The only apps that I use often on other platforms that are not on WP are Amazon Instant Video, Google Play Music (of course, this app won't be put on WP, but any music locker would work. I don't understand why Xbox Music doesn't have this functionality, because it really should), and a couple games, like Threes, Clash of Clans, and Badlands.