It is relatively straightforward to retrieve an image from the phone's camera app using an Intent, where that image is in the form of a Bitmap.
I don't know if this is an appropriate question for SO really but is it common practice to just save the entire bitmap as-is? Or do most people compress / resize it down?
You tend to save it using Bitmap.compress, which will compress it for you. Feel free to use PNG which is a lossless format, so no quality loss will occur when you reinflate it.
Of course if you're using an intent to get it from the camera, its usually saved to the file system already. In which case that file is certainly compressed already.