idk why the subject of a camera cam up but heres suggestions anyway:
1. what about a replicant option? there have the main camera on the samsung i9100 reverse engineered. no video due to no hw encoding but it can take photos. snags: non-free bootloader :( , no gps. modem is separate from the cpu and ram but is not as isolated as the GTA02/4.
2. cheap non-free action cam without wifi? check out the mobius and theres many other ones, in a gopro formfactor with a screen, idk which is the best of them. there is also Firefly Q6 [2,3] which i find of interest personally due to its form factor and that it has a little menu screen. there is also FOXEER Legend 1 which is has a better video enocde profile [4]. I have a mobius, been happy with it. snag: have to make effort to plug into device and edit the config for low light mode when in dark outdoor places. hench my attraction for the firely q6 and its menu screen. Modbis firmware as received many updates. webcam mode needs more work on it still but all other features i think have been debuged, ive not came across any bugs, put it that way. [6] mobius is a bit more expensive now. so i would try a newer one. snags: these action cams tend to skip on emi shielding, know to be a problem for gps in drones.
3. perhaps the freest and cheapest option, get a Zipit Z2 handheld computer and use a usb 1.1 compatible webcam. i can send you a goodie bag of bits in order to do this. (ie breakout connector, heck even wired up for ya.) check out #zipit irc on freenode and [5] . snags: non-free wifi. but mozzwald has auto build system setup and can compile missing kernel drivers, hes already done athk free ones on request :).
[1] http://redmine.replicant.us/projects/replicant/wiki/GalaxyS2I9100 [2] http://www.gearbest.com/action-cameras/pp_451141.html?wid=21 [3] (120dec version) http://www.gearbest.com/action-cameras/pp_360144.h tml?wid=21 [4]http://www.gearbest.com/fpv-system/pp_452894.html?wid=21 [5] https://mozzwald.com/zipitz2
[6] http://www.banggood.com/Mobius-Full-HD-Sports-Camera-1080P-30FPS-72 0P-60FPS-For-Multirotor-p-90648.html?rmmds=search