iSequence is a beat making app for your iPad. It has an 8-track sequencer, on board effects, and 160 instruments to choose from. Instruments range from a collection of acoustic kits to leads, pads, and more. You can also expand your sound library via the app store with additional sound sets for $1.99. Available effects include Filter, Reverb, Flanger, Delay, Ring Modulator, Equalizer, LO-FI crusher, live looper, Distortion.
Here’s a snippet of a cool beat made using BeatPad 3.3
BeatPad 3.3 ($6.99) is a drum machine with a built-in 4 track audio recorder for you iPad. The newest version comes with more sounds than its predecessor and even boasts a slightly cheaper price tag (supposedly).