Find the Jet International digital subscription app.

IF you have a JR or Spektrum radio, the telemetry app for the STi. I'm still looking around for more uses but a RC unrelated app.......
Angry Birds, for those down times while waiting for the flight packs to charge or someone else flying. CAUTION..if your wife or loved one gets a hold of Angry Birds, you might not get to take the iPad to the field for the rc related task you originally had planned uses for.