ReSlice - Slice your audio with an advanced, rhythmic arpeggiator and FX.
Sampulator - Make (and record) beats on your keyboard
nlog Synth - Professional Virtual Analogue Synthesizer ::: check nlogmusic at YouTube :::
Studio Amplify - Create cutting edge music and audio apps
cassini - Polyphonic Synthesizer for iPhone/iPod touch
Logic Pro X - Music production.