Grooveshark (Free) by Grooveshark is the official app for users of the streaming music service. Grooveshark joins the ranks of Pandora and Last.fm as its official app hit the App Store recently. It allows users of the service to login with their accounts in order to access playlists and favorites, although you can create an account when using the app for the first time. This starts a 30-day trial of the premium ‘VIP’ account, which gives mobile access