The issue is that WebCamTexture.Stop() frees internal memory buffer used by GetPixels(), but doesn't mark it as deleted. So subsequent requests by GetPixels() will write into freed memory, as well as crash when it tries to delete the buffer a second time when WebCamTexture is GC'ed or Stop() is called again.

Unfortunately, the only workaround is to never call Stop() and make sure that WebCamTexture is never freed. 4.6 users can consider to revert to 4.6.4p1.

To reproduce:
1) Download and open project
2) Build and run on iOS
3) Press capture button
4) Press Unload button
5) Notice crash

NOTE: commenting out line 24 (which calls GetPixels()) seems to not cause crash

Reproduced on 4.6.4f1 and 4.6.2p2 using iPad Air (8.1.1) (no difference when using mono or il2cpp)
Doesn't reproduce on 4.6.2p1