The simple answer is that a large enough & powerful enough magnet could. But, it is highly unlikely that your average household magnet would have an adverse effect, and the magnets in Mous phone cases are not powerful enough to cause any substantial interference.
What problems do magnetic phone cases cause?
This includes messing with the digitizer, creating dead spots and distortion, and potentially affecting sensors such as the magnetometer. These effects are temporary, but in severe cases could make the device hard to use, or result in misinformation from apps dependent on affected sensor(s). Permanent damage.
Are magnetic cases bad for phones?
No, magnetic mounts won't damage your smartphone, at least won't damage them from the inside.
Are magnetic cases safe?
Yes, your cell phone is completly safe mounted on magnetic holder or inside magnetic case. You may have seen writings and warnings that your cell phone is not safe if it is close to a magnet, or that magnetic will interfere with your smartphone GPS, batter, or something similar.
Are magnetic holders bad for phones?
While your screen, memory, or battery aren't threatened by magnets, your phone's compass can be. A powerful magnet can interfere with your compass reading and even slightly magnetize some of the steel inside your phone. This magnetization could then continue to interfere with future compass readings.
Are magnetic cases bad for iphones?
The magnets used as enclosures for iPhone cases are not strong enough to cause damage to most electronics. The stronger magnets used to hold an iPhone to a stand or belt attachment won't damage to the iPhone's storage components, but they may interfere with other components -- image stabilization, for example.
What is the point of a magnetic phone case?
A: If you plan to use your phone with bike mounts, car mounts, or other accessories, a magnetic case is a handy accessory to have. Magnetic cases can also help to keep your phone locked onto a wireless charger, especially in the case of Apple's MagSafe line.