Scary occurrence this evening. Flying my 3rd flight and suddenly I see “command timeout” warning and the screen goes blank. I was about 200 ft up and 1500 ft distance and had no control. Tried atti mode, restarting iPad, turning off controller and back on...no go. Luckily, hit s2 switch twice and return home initiated. Tried to cancel as I like to hand catch but still couldn’t gain control. Landed w/o incident...got lucky. Any ideas on what may have happened? This was a first for me in over 200 flights. Thanks.