Samsung manual says not to use a case that has a magnet on/in it.
I recommend reading the manual before you do anything else, lol.
Never buy those hard, clear plastic (aka crystal) cases as they mark the phone somehow and let dust between the phone and plastic anyways.
You can buy sheets of screen protector that you can cut to shape, I might do that at some point, but it will interfere with the touch a bit.
Since the phone is the size it is, I have resorted to storing it in a full size sock rather than a phone sock, until my Noreve case arrives.