People have varying different opinions of cases that have a magnetic catch in that they can affect the phone in a few ways, but then some say it doesn’t affect theirs !
Personally I prefer not to use cases that make use of a magnet which also includes official Samsung options.
So a case is normally chosen to suit the wants and needs of the owner.
Some want full cover flip cases that also include a Credit Card Slot etc.
Some want TPU type clip on cases to add grip.
Some want enough rubber and plastic around it as they work in the building trade / outdoors etc , or are prone to dropping their phones. Some of these cases would survive a Nuclear Winter -lol- but do take away from the beauty of the phone.
Disposable Income / amount of money wanting to spend on a case determines what’s available too.
I’m in the minamilist category group. 
I want something that adds some protection and adds grip but keeps to the beauty of the phone as much as possible.
Therefore i use....
- Rhinoshield CrashGuard Bumper. [ imported from the USA ]
- dbrand Black Dragon Back Skin. [ imported from the USA ]
- Official Samsung Film type Screen Protector. [ Samsung Experience Store]
Sometimes finding the the right case for you is hit and miss.
Tip > Also look at what protection the case gives via the amount of the case that sits above the screen display so if the phone is placed screen side down the screen display itself isn’t sitting on the surface.
Have fun. 
