You're practically begging for public embarrassment. I like that.
I wouldn't use such an app, but a lot of apps people really like are just quicker or easier ways to do things you could already do on the phone before.
A way I can see a majority using this is if the app can be easily activated/deactivated before driving. So that if driving one button would set u up and you wouldn't have to mess with the phone as much. This would be useful for people who don't use bluetooth. So there, I think that is a good enough reason for a dev to make one
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