I've had a few lockups/crashes with the release version of C3 on my HTC One. It locked up one time when I tried loading my caustic community jam track and I had to force quit it. I submitted a report for that one and the phenomenon has not been repeated.
The more serious one which I can repeat is C3 crashing when previewing samples from the beatbox. It seems to be to do with trying to preview a sample when one is already being previewed. I was trying to do this with some breakbeat samples when auto preview was enabled.
It doesn't happen with all samples, but I can replicate it every time if I enable auto preview, go to the beatbox presets folder->606 and tap through the samples really quickly, so hopefully others can confirm without needing my sample library!
NOTE: I tried the same thing with the PCM and it did not crash.