iPhone put on Magnet bad?

Hello all,
I have a quick question of understanding.

Is it harmful to put a magnet on the back of an iPhone XS to attach it to the cradle in the car?

I think rather no, but am unsure. Read a lot and it is not clear.

Thanks for your help

You’re proposing to “glue” a magnet to the phone? I would suggest you don’t… for many reasons unrelated to performance of the phone. You don’t want the phone being attracted to your keys or other metal things it gets near. The normal solution for this is the reverse. You put something metal that magnets are attracted to on the back of the phone (hopefully on a case) and then put the magnet in the car to attach it to.