Ever been in a situation where there are no musical instruments around and you need to get a key? This is a great and simple app for musicians and singers. This mini piano allows you to play any note within one octave between C3 and C4. Give singers their notes, find what key a song is in, tune your guitar or other instruments. It's your personal mini piano you can take anywhere you go. Just for clarity, this is NOT a multi-touch application. You can only play one note at a time.