Android Phone Camera Basics

What kind of phone do you have? That will help us figure out the specifics.

If it's anything like mine (Sprint, Android, Samsung S7), if you go to Settings (the gear-like icon), there's an option for picture size. That's where you can specify the dimensions and resolution. Mine has several options --I have selected "4:3, 4032x3024". The options you listed are only for the aspect ratio -- effectively square, widescreen, and 4x3 (old tube-style television dimensions).

If your pics are huge but grainy, it sounds like you have a focus problem. Can you tell how many pixels high/wide your images are? If you use the image optimizer here, it should tell you before you make any changes. If your images are about the same number of pixels as mine (4032x3024), it really does sound like focus -- that's something you should be able to control as you're taking the picture.

If you have a smaller number of pixels (e.g. 800x600), you'll need to adjust the resolution to something closer to mine. That's probably in the Settings. With that few pixels, no amount of optimization will make the pictures appreciably clearer.

1:1 is the best way for coins. You will not need to crop.