Many of the best cell phone sensors are off-the-shelf Sony sensors that individuals can buy in reasonable quality. The “magic” of cell phone cameras is the combination of these decent sensors, a lot of processing (that you don’t want), and really amazing lenses (that, in a microscope application, you’re replacing with your own — better to go microscope optics to focal plane than microscope optics to cell phone optics to focal plane). Certainly at the hobbiest level cell phone cameras are amazing, but I suspect even “advanced hobbiest” or whatever would prefer the same sensor in a C mount.