1. What does refurbed mean?
2. Ipad 4th gen uses the new lightning port, which is alot slimmer than the old port, so you'll need a converter. Then everything should work as usual, I've never heard of ios software that isn't backwards compatible, only newer software not running on the old ios versions. Ipad4 comes with ios6 from the factory, the latest on mine is 6.1.3
The 1st gen has bad CPU and graphics capabilites compared to the later ones, so synths and programs made for the later ones suffer badly.