This free version, will let you do one flight at a time. Secure your device in your aircraft, pre set the amount of fuel on board, and timers will let you know how long you can fly. You will also be able to review your fuel consumption at the end of the flight and the air time, flight time in hour format and decimal format.
The full version allow you to creat many aircraft, and use it with out re-enter all the informations. The full version will allow you to do as many flight as you want, and comme back later, to retrieve the flight information.