Same here, happened on last flight. I only wanted a night / sunset shot. Went to a park, flew straight up to 400 ft and was making camera adjustments for aperture and sh speed, then blank screen and DISCONNECTED! Nearly full panic, then I moved the sticks and it responded. I was lucky I could see its lights straight up on clear night and saw the response to my commands. Flew it back to ground immediately. Never reconnected. Attempted on / off of aircraft with new batt, and RC but no. Then I restarted my Samsung Galaxy S5 and then the aircraft and RC and got a connection. Packed up and went home. Still leary, but I need to know so I'm flying today in large area where I can always get to it. I did a fly over water shot and it was AMAZING so I want to trust this new toy / tool of mine and keep it going. I simply have issues with $1500 flying away.
Oh, sidebar....saw another post about drone finder tool and have seen it before. EXPENSIVE! I'm considering something called Tile. Only $20 or 4 for $70 and can stick it to it and may help find it. I have to look at it again, but I think range is decent and I think it also sounds off if you trigger it to from your phone. Comments?