If you like sound of TB-303 and acid techno music you can turn your phone into endless acid techno "mix" or "live" generator.
Just turn it on press Start and listen as a usual player but music will never end.
Main theme or "track" changes on every 3-4 minutes automatically.
To play next track manually tap Reset.
You can record created music - tap on R icon.
Also it has "mute" feature - tap on gear icon and you can mute chosen instruments and use app as a synth samples generator for example. Recorded parts always loop seamlessly.