drumbit - A very easy to use drum machine.
Figure - Propellerhead creates world-class software products and services that inspire music makers and provide the foundation for a worldwide creative musical community.
Sampulator - Make (and record) beats on your keyboard
SoundGrail - SoundGrail Music App designed for pianists, guitarists, and DJs.
Type Drummer - Drum by typing
Splice - Music creation, collaboration, and sharing made simple.