I've been using Control for a remote focus unit for controlling theatre lights and I've noticed that it crashes pretty consistently. As long as I keep it on the screen it's fine, but when I switch applications and then switch back to Control it usually crashes as soon as I press a button in the interface I designed.
When it crashes I get dumped out to the iPhone's app selection screen and I can restart Control immediately but it has usually lost the destination from the list so I have to re-enter it, and then reselect the interface I was using. Once I do that it works fine, but if I switch apps again and then come back to Control it usually crashes again.
It seems to be related to having Control in the background for a significant period of time and then switching back to it. This is typical of lighting focus where I want to turn a light on and then spend a while adjusting it before moving on to another light and also when I'm busy with other things mixed in with focusing.