Wolfy Can I go back to the default OS?
GrapheneOS (aka GOS) is extremely easy to install and just as easily reverted to stock, as others stated.
Wolfy Will it still be able to connect to my car?
I've only tried android auto once and it seemed to connect and function just fine, but I can't attest to it's full functionality.
Wolfy Is it a big change from android im used to?
Generally, no. If you install Google Play Services/Play Store (recommended for most, especially beginners), it'll look and act nearly identical to most other Android phones. This is the beauty of GOS! There may be some settings tweaks, app choice changes, etc., but overall should feel very familiar.
The UI is based on AOSP, which stock Pixel is also based on. However, stock Pixel makes a number of changes to the UI. So, while everything should be where you expect to find it, there will be very minor differences.
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