I don't want to use a raspberry pie, for now. I want a simple design as small as possible without sacrificing quality & device safety. So what module do I need to build such a device? I have selected a camera module & a microSD storage module named OV7670 & catalex respectively. Of course I will need a 3.7v li-po battery. I am not think of commertializing it. Right now its just a project. BTW if want to make my device smaller than gopro camera & as small as spy camera as possible.