No luck there. It is an Asus tablet, and Asus seems to be terrible about Android updates. I can’t even get 4.7 (or, whatever the version was after 4.2.2).
There seem to be old versions of Avenza available from:
What Avenza version do I need so it will run on my 4.2.2 Android?
I have used Avenza extensively with this tablet…but, I had to do a OS re-boot this winter and only now have gotten around to trying to load Avenza.