I would expect you’ll be using the tablet for more than just navigation, such as watching videos, listening to
music, keeping lists and also
email / surfing the net when in range.
Consequently, I would suggest using a tablet that meets all of those needs best.
My observation is that either Android or Apple
work fine.
I’ve subscribed fully to the Apple ecosystem and hence I use an
iPad.
Works well for me, however the major drawback is that I can’t run
OpenCPN on it

.
Works well with
Navionics and I expect most other navigation apps.
If you do go down the
iPad path, make sure you get a model with
GPS capability!