They're not used to program the FMC though, the digital flight bag is for airport charts, performance calcs and en-route charts only (and the FMC does the performance calcs anyway).
Airline pilots don't do very much pre-flight planning, they fly the route given by ops. Us lowly PPLs have to do all the planning ourselves however, and yes, you can do it on an iPad, but you still need to pop it onto the Garmin in the cockpit manually if you want *it* (it being the linked autopilot) to fly it rather than you.
Yes, I'm well aware of it, the whole point is 5 years ago, this wasn't even allowed. Now tablet devices are becoming more and more prevalent.
For example look at the rise of the G500 or G1000 in the cockpit of even the 172's of the world. The same thing is happening with the use of tablets.
The FAA approves tablets for nav maps, flight bags and SOME systems monitoring currently. What are they going to allow/support next year? 10?
Hell I learned to fly on a J-3 built in 1947 for sake... there was NO way I could have seen flight nav, flight training and flight control taken to where it is today. So yeah, I can totally see the use of a mobi-glass device for a lot of flight stuff.
I can very much see the future going just this way.