FYI, there are also offline and free locally running apps that you can use:
https://wiki.openstreetmap.org/wiki/Routing#Mobile_device_so...
I used OSMAnd and it works better than Google Maps for my area.
It might be better in other places, but it's a long way from replacing google maps for me.
It's not entirely free, namely map updates are limited without a subscription—though I haven't checked if it's the same with the F-Droid version.