It's just the self control portion, don't even need to remove the smartphone, but it helps. Technically mine's still android but it's so stripped down it's basically a dumb phone with poorly working gps and Signal.
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I also drive in slience, except I have an electric car, so it's even quieter 😂
I have a smart phone, but I don't have an addictive personality (the opposite actually), so it's really easy to not use it if I'm not using it.