Activating/deactivating the camera definitely falls under the category of "things that should ideally never crash the operating system but is eventually likely to happen".
The integration of the hardware and the software drivers required to drive that sort of definitely increases the chances that there's a bug at some level that may well be lower down than the camera app itself.
I never saw any sort of correlation between wifi/3g and random crashes (not to say that I think you're wrong), though it does seem to me like the wireless drivers in 4.0.2 are definitely buggy. Typically after about 2 days of uptime (if the phone hadn't crashed by that time) I would start to see either the wifi driver get into a wedged state (I'm guessing based on log messages) where it would cease to function and require a reboot, or the 3g data would quit working until I cycled airplane mode (is this the data bug I've seen discussed a bunch?).
Anyway, I guess the reason I'm communicating all of this is just to further suggest that 4.0.2 seems so buggy in so many ways that are related to operating system-level software ways that I highly doubt any single app or set of apps is to blame for instability.
(And I'm approaching 24 hours on 4.0.4 now, which seems vastly improved in a number of ways. Let's hope this fixes everything.
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