Fly your Parrot AR.Drone 2.0 with AutoFlight. Requires the Autoflight software: http://lbpclabs.com/autoflight/
Note: At the time of this writing, Autoflight is at preview version Alpha 0.2. It seems to be a little unstable, and would occasionally get into a state where the app could no longer talk to the drone without a reset.
Doing things in this order generally worked: 1) Connect to drone via wifi 2) Launch Autoflight 3) Have you fun 4) Close Autoflight 5) Disconnect from wifi.
Note that the Parrot AR.Drone 2.0 will not take off with less than 33% battery. AutoFlight will not tell you this, so check the battery level if it's not taking off.