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You'll need an otg adaptor and something like this, not sure about the camera thing, that will need more research.
Still need to slice in a computer though, or some cloud based service.
There's currently no slicing software available on any mobile platform so you'll need at the very least a raspberry pi. You can definitely print from a tablet or phone connected to the printer though, this. Also, why not just run the print from and SD card?
I literally just did a google search for "android 3d print server" and found that. I have not used it, didn't even know it was a thing five minutes ago. Give it a try. Be the guinea pig.
Well, there's this, but it only uses gcode output. You'd need something to create the gcode. From what I recall, OnShape has a slicing plugin, and is WebGL based, which means it could work on Android.