Recently I encountered one problem. I was running with PDA in my backpack with display turned off and locked keyboard when phone (in PDA) started ringing. Problem was that OS switched to phone application pushing Run.GPS in background, but display was still turned off.
Luckily I have assigned hardware button tu Run.GPS, so I could restore application, but without it only solution would be reset.
Can it be changed, so when Run.GPS loses focus it would turn on display and probably backlight too?