I have an Android mobile with a 5MP camera. Is there any way to save raw images (similar to Canon CR2, Nikon NEF, etc.) from my Android device?
Unfortunately, unless someone (almost certainly the sensor manufacturer in conjunction with the camera manufacturer) has provided methods to get RAW data from the sensor level all the way up through the Android stack, it's going to be somewhere between very difficult and impossible.
Even if you did get RAW data, most processing suites probably aren't going to know enough about the sensor data to do a good job of processing it into a decent image.