The only reason we got the sat nav, was the level of accessories needed to get adaptive cruise control (which is what we wanted) included it anyway.
It also includes the software to run a "browser" on the screen. If you pay £200 for the Citroen wibble-city adapter, plus £30/month subscription. You have to do this, as they have nobbled the bluetooth networking to reject anything non-Citroen (like a tethered phone).
As it happens, not having had a "browser" fixed into a car before, we don't miss it. But we do have (two) which we can carry out of the car with us ...
Someone upthread mentioned Google ... there is a feature/product of Android called Android Auto (not to be confused with "Google Drive") which is a protocol to connect your Android device to your Android-Drive enabled car, and run the screen etc from your tablet.
Personally I'd hope this is the way forward, rather than every manufacturer trying to compete and inevitably failing dismally.
www.carwow.co.uk/guides/choosing/which-cars-have-android-auto
You can run Android Auto just on your device. Personally I don't like it, as it doesn't allow to divert calls/texts to voicemail when driving, and it's integrated with Google Maps which isn't very good.