Hello Orcadolph,
Thank you for using Apple Support Communities! I understand that you want to know if it's safe to use a magnetic case with your iPhone. I would be happy to help provide more information to consider.
Magnetic cases can cause interference with the camera on your iPhone so it's suggested that you avoid using any magnetic accessories, including cases to avoid potential issues:
Magnetic accessories might interfere with iPhone cameras - Apple Support
If you wirelessly charge your iPhone with the magnetic case on, here is more information to be aware of:
How to wirelessly charge your iPhone 8 or later - Apple Support
- "Wireless charging uses magnetic induction to charge your iPhone. Don't place anything between your iPhone and the charger. Magnetic mounts, magnetic cases, or other objects between your iPhone and the charger might reduce performance or damage magnetic strips or RFID chips like those found in some credit cards, security badges, passports, and key fobs. If your case holds any of these sensitive items, remove them before charging or make sure that they aren’t between the back of your iPhone and the charger."
Cheers!