Now, it could just be my damaged iPhone, (It went for a dip in the swimming pool about six weeks ago, documented here.) but this afternoon I noticed that all of a sudden, several of the apps died. Each of the affected programs would load their initial screen, and then within about one second, vanish. The phone went back to the home screen. Programs affected were Sketch (which I hadn't tried before) and Tile Sudoko, (which I had) and a few other programs. I was disturbed.
First I feared that I'd run out of memory. I deleted a video. No change. Then I wondered if it might be some specialized memory pool that was used by all apps. I un-checked a few apps in the iTunes list and re-synced. No change.
Next up on the remedial list was a powerdown and then a reboot. No change. I then did a backup and restore.
Somewhere in that process, I realized my house internet had gone down, so I brought it back up, but the total wipe and restore was already underway so I had to finish that. After that, everything worked again.
So...was it a memory corruption that caused the problem, or was it the network outage? I suspect the network, since the wifi was up but there was an outage several boxes down the line. The phone knew it had network, but stalled and then the programs crashed.
Do Sketch and the sudoku program check in to the home website on the first usage (or every usage)? I'd like to know, because that would explain the problem, and highlight an error mode that ought to be flagged.