Any sequencer that accepts midi calls will do, in my case i am using ableton live on my Macbook.... I only use the ipad for the interface, which is an app called TouchOSC which also is available in android...

On the ipad you could also make it work with a random sequencer and the midibridge app witouth any need for a PC , however i dont think that app is available on android..

I am currently using my ipad set next to the screen of My Tyros, using it mostly for the touch interface, since i moved from my windows based daw with touchscreen to my new macbook my ipad is mostly making up for the fact that my macbook does not have a touchscreen. But my recent research got me to believe that the ipad can function as much more then just the touchinterface..