Here is a screen shot of an iPhone screen. The bottom four apps are my music apps.
From left to right: GigBaby, Decibel, Pocket Piano, and TrollDrum
My home screen has my favorite app – Chronology, the ultimate timer.
GigBaby is a cool 4-track recorder with a great drum machine built in!
Decibel is great for measuring your volume. 
I like having Pocket Piano with me just in case I want to transcribe something or plunk out an idea.
And finally, TrollDrum is a MIDI drum player that I just started experimenting with. It also has a server library of rock tunes to download.
