Slight Android weirdness, help!

Eldest has a Samsung Galaxy Ace, GT-S5830i with Android 2.3.6 installed. It was originally supplied as a locked contract phone by O2 to my mother in law, who had it unlocked and passed to him when he started high school. It now has an Asda PAYG SIM in it.

Last night it started repeatedly bleeping notifications. I don't know if these were mail, text or one his games. I tried to get into the phone but after doing the unlock swipe, the phone was only responsive for 20 seconds before going back to the lock screen (via a very brief appearance of the O2 blue bubbles ident). In fact if I left the phone alone it repeatedly showed the lock screen, followed 20 seconds later by the O2 ident, followed by the lock screen again.

I left the battery off it overnight and tried again this morning. No joy. Eventually I did a hard reset and the handset is behaving as it should, with one exception: the wallpaper has set itself to an image from a free game called Pou (a kind of cyber-pet app) which in all other respects has been erased from the device, exactly as it should have been during the hard reset.

Is this suspicious in any way? He has had that game installed on the phone for weeks without any apparent ill effects, but how can any part of it, even an image, survive? It wasn't on the SD card incidentally, as I removed this prior to the reset. I have since also reformatted the SD card.

To cap it all, having solved the problem only by taking the nuclear option, I still don't know what caused it. Does anyone know what might cause that sort of behaviour on an Android phone?

[qasdfdsaq]

Originally Posted by Chris

To cap it all, having solved the problem only by taking the nuclear option, I still don't know what caused it. Does anyone know what might cause that sort of behaviour on an Android phone?

The behaviour itself sounds like a low level OS or system component hang. The watchdog timer sees the application or driver become unresponsive, and soft-reboots the system. As for what causes it... could be anything. Incorrect settings (usually only achievable by tweaking with hidden/advanced settings), hardware failure, overclocking, water ingress, faulty SIM card, dodgy audio driver, are all examples I've seen causing such behaviour.

[Hom3r]

try an app called Airpush Detector it will tell you if any apps have installed "other" items, and will allow you to easily uninstall them.

The only other thing I can think is that the phone is on its way out.