Oh man there is so much that you can do on an iPad for recording ideas... I use an apogee-jam, audiobus, bias-amp to custom tailor my tone, jam up pro with my bias-amp preset, wow-filter for effects... The list goes on and on... Hardware wise apogee jam is my preference. You can run your bass through a pedal first... Once you have nailed the tone explore it all... Loopy HD is great for looping ideas. There are a few DAWs out there for multitracking as well. Plenty of drum apps to jam to as well as synths galore... Once you are in you will be surprised...