It crashes for me every time I take somewhere between 60 and 75 frames with the main camera. With the front-facing camera, I can shoot forever.
In the iPhone Settings (somewhere called Diagnosis & Usage), I have a bunch of LowMemory warnings. I'm using an iPhone 4S.
It seems I enthusiastically chose a larger buffer size that appears to be having some issues on some devices that have a lot of memory pressure.
If you reboot your phone, as awful as that sounds, it will likely fix the issue.
EDIT: I've just submitted an update to Apple that uses a more conservative buffer size.
This aspect is hard to get right: I once used an adaptive buffer size that heeded to memory warnings, but that meant that the buffer filled to lower levels than a conservatively sized buffer.
If only iOS had an opt-in for an *alloc returning 0 instead of these warnings, or at least notifying us of how much space left before we're SIGKILL'ed.
I recently read an article here on HN that briefly touched on memory management under iOS and especially the problem of apps getting killed, maybe it is interesting for you: http://sealedabstract.com/rants/why-mobile-web-apps-are-slow... (scroll down to "How much memory is available on iOS?")
