You cannot start a car with a suction cup.
I can’t start my car with my car’s app either.
If you really want to be picky about it, block out the unlock feature and any potential ‘phone as key’ functionality. Leave starting the air conditioning and information.





It means that if you are so obsessed with protecting a user from making an informed decision about their own security, then you could gracefully degrade in your ‘horribly insecure context’ instead of just bombing out completely.