Atom is a “piano roll” sequencer for making music on iOS. A piano roll is named for the software used to run olde worlde player pianos. It’s a roll of paper with holes punched in it. As the roll moves through the piano, the holes are read by a “tracker bar,” and the corresponding notes are played.
Imagine such a sheet of paper in the digital realm. That’s a modern piano-roll sequencer, and it’s a commonplace way to control software instruments. Atom brings some amazing tricks to the piano roll. It’s also an Audio Unit (AU) app, which means it can work as a plug-in inside your favorite iOS Music apps, like Cubasis and GarageBand.
