I just flew across country in my private plane, using the ipad as my SOLE source for charts and plates (with backup paper, just in case). Worked beautifully, and flew many instrument approaches without a hitch. Had a charger, but didn't need it, because on the long stretches of straight and level flight, you can easily close the smart cover, to conserve battery power, if you need to, and you don't need to look at the charts except when changes to routes occur, or during takeoffs and landings. Don't forget that the aircraft avionics are doing all the flying, and the ipad is merely used for situational awareness, not for any primary flying. Software is now being tested to bring inflight weather mapping, but commercial planes have radar anyway, so, once again, an ipad enhances safety, and removes the paper chart distractions. Anything that can be done to remove workload is a benefit. I specifically bought the ipad2 to use for flying, and it has been worth every penny.
Who's software package have you been using? I see United are going for Jeppesen, but I believe there are multiple options out there.
I'm about to start flying again after a year out (taildragger training starts in 5 hours!) and was thinking about subscribing to something like this, instead of heading to the pilots shop to update all my charts/AFD etc. I'd appreciate your advice on what you've found, what you like and don't like about it etc.