The main use case for my current iPad is to connect the audio-jack to my guitar amp and use GarageBand - which currently works great because I can charge the iPad at the same time. I guess in the future one can only use the audio out OR charge - which is a shame.

Edit: No, I can't really use bluetooth here since a) 99% of guitar amps have no BT support and b) the latency is noticeable.