This is what the developer said:
I got inspired and wrote my first Android music app. The app is a USB MIDI Grand Piano App and 100% free (no ads, no fee, no crazy permissions, no nothing). The app uses real samples, supports sustain pedal, metronome and makes really everything for a low latency.
If someone is interested, I would really love to hear your feedback:
https://play.google.com/store/apps/details?id=com.musilethics.piano
Many, many thanks
Google Play Info:
USB Piano HQ
Connect your USB Midi Keyboard with the USB Piano HQ app to get an authentic piano feeling!
Features:
✓ Free and without ads
✓ High Quality samples
✓ Low latency
✓ Support for 84 keys
✓ Metronome
✓ Drum/Groove Machine
✓ Real reverb
Requirements:
- USB Midi Keyboard / Piano
- USB OTG Cable (also known as USB Host Cable)
How does it work:
You only have to connect your USB Midi Keyboard with your Android smartphone or tablet via USB OTG cable. Thats it!
Problems or wishes? Please contact support.
Audio by Superpowered