MIDI Controller is a free Android app developed by Volcano Mobile SNC. It is a versatile MIDI controller that allows users to control their MIDI-compatible devices via Bluetooth. The app has various features such as buttons (Notes, CC, Program Change, Real-time, Bytes, App), faders (CC, App), X/Y buttons (CC), channels mixer, MASTER Clock, metronome, and MIDI connection (USB + Bluetooth). The app also has a premium version that offers multiple sets of controllers.

MIDI Controller offers an easy-to-use interface that is suitable for both beginners and professionals. The app's buttons and faders are highly responsive, and the X/Y buttons are perfect for controlling effects. The channels mixer is a great feature that allows users to control multiple channels simultaneously. The app's MASTER Clock and metronome features are helpful for keeping track of the tempo and rhythm of the music.

Overall, MIDI Controller is an excellent app for musicians and producers who need to control their MIDI-compatible devices via Bluetooth. The app is reliable, easy to use, and offers a wide range of features that make it a must-have for anyone who wants to control their MIDI devices from their Android device.