TonePlane Publisher: Theodore Mitchell Genre: Music Released: 24 Jul, 2014 Size: 520.0 KB Price: FREE! Click here to request a review of this app App Store Info Description From left to right, the pitches increase by octaves. From top to bottom, the pitches decrease by fifths. Have fun. What's New in Version 1.2 More shades of gray to distinguish keys Screenshots Screenshot 1 of 2