Melody Box Lite is a free, easy-to-use music composition app for the iPhone and iPod Touch. With Melody Box Lite, you can write catchy melodies using its monophonic Sequencer, a powerful and simple way to construct new musical phrases.

To change the notes, just shake your iPhone, and Melody Box will generate patterns for you. If you don't like what you hear, simply shake again to try something new! You can also flip individual boxes upside down by swiping a finger over them. Copying and pasting between boxes is a breeze: just push a finger down on the box to copy, then touch the destination box with a different finger to paste.

With the Effects Mode, you can change the melody to be as serene or as scorching as you like! Simply move your finger across the pad, and you can quickly alter how your composition sounds. You can follow along with your melody and distort certain parts, moving your finger fast or slow to change the timbre.

If you want more functionality, upgrade to the full version, Melody Box. Get more control over what you write, and you can change the tempo too!