completely non reliable from my experience. i returned to the game this past july. my airports, aircraft, level, everything was gone. except i was still in #toucharcade group in game. Contacted support. Friendly response offered to help restore based on most recent screenshots of my last play with old fleet. Replied with screenshot link, never heard from them again. -shrugs- the games so much fun though that 3 weeks later i had my fleet back up from regular gameplay and never bothered pestering for a followup lol.