I started with a direct query re a specific on Bluetooth pairing between my iPad 3 and new Sony Xperia J smartphone.
This is by way of the introduction requested.
I use iPad for browsing, games, video and catch-up TV and an iPod for music/audio etc. WiFi is so plentiful that I don't use 3G. I have the phone and my work Blackberry if I need 3G. I've not bothered with 4G as I won't be streaming much video other than via WiFi. Some specifics are that I use SlingPlayer when I'm travelling in Europe (which is constant) and I have a few music studio apps to supplement my home recording activities where I have a lot of gear including digital multitracker (Boss) and a host of gadgets, processors and instruments. I've tried iRig and AmpliTube but have yet to be really turned on by it especially in comparison to what I can do with the stuff I already have. I was attracted by its portability however lugging a guitar and keyboards around is impractical and as said I've got something better at home. The Virtual Pro Piano and Music Studio Apps I have on the iPad are fine for jotting down ideas when travelling. Maybe I'm missing a trick with iRig/AmpliTube but I feel it's something more suited as an introduction/stepping-stone to recording etc. I'm expecting to get shot down in flames here.