If you're an iPhone or iPad user, you can with the app Bebot turn those devices into powerful synthesizers.

Bebot is a musical instrument that anyone can play. Instead of a keyboard, it has an easy-to-use touch control system. And it's all built into a friendly animated robot, who performs your music while you play.

Although it looks simple on the outside, inside is a powerful synthesizer engine which lets you create and edit your own sounds and apply effects.

The touch control system lets you lock in a scale so that you'll never play a wrong note, making it easy to play on an iPhone, and even easier on an iPad.

I became aware of this magnificent app after having seen Norwegian comedy duo Ylvis pranking gym visitors with an app similar to this. The 2.12 minute mark gets me everytime!