This does explains why a dedicated device is somehow better, if fine tuned for the scope, and why companies like Garmin and TomTom use their own OS version
(fine tuned out of linux, I guess).

I've always wondered if there are no sunlight readable devices (or perhaps separate displays) running a normal Linux environment.
In the past Familiar Linux ran on the 3870s (it still does, but its all very outdated), but that ended some years ago.