Groovebox: Beat & Synth Studio - Make Music & Play Instruments
Songlio - Free musical guessing game: race friends to name that tune
Scratch Track - Scratch Track is a simple and powerful application that offers services as a recording app to capture song ideas.
SongTrivia2.io - Songtrivia2.io is a browser and mobile blind test game that allows you to play in real time with your friends or against strangers. Several musical themes, difficulty and game modes are available to create lots of different musical quizzes.
BeatStyle - A mobile recording studio!
SongPop - The world's biggest music trivia game. Now even better.