Don’t place your magnetic smartphone holder above where the ignition key/button is.
Magnetic phone mounts are great, except physics still plays a role, like when having to suddenly brake and your large smartphone weighs just enoughjust fall down, hitting the key in your igntion, and/or in trying to catch it during freefall, you accidentally hit they key. This can cause the car to think you’ve decided to turn off the engine, even when cruising at 60mph.
My windshield is too far away to mount the phone to, and the dash doesn’t have a good place to mount it except right over the gauge cluster, but I like outwards visibility.
Time to look for a longer arm with a mechanical grip.