I tried running Navigator on a Google Nexus 7, which is a nice bright tablet. Android 11 on that unit is a 3rd party Android build. I worked on it for a while and could not get Navigator working correctly. So I gave the old Nexus 7 to my grandkids and bought a Samsung Galaxy Tab A7 Lite 8.7 inch display and all my Navigator issues went away and it runs smoothly on the current March 2022 Android 11 build.
The A7 Lite has a bright display and can be purist for around $100.
I did like the idea of the Nexus but it is outdated hardware with a 3rd party Android build. You might want to look at the Samsung just my .02 worth.