Rob from SkyDemon here!
If you are looking for a low cost tablet, you could do a lot worse than the Tesco Hudl2. It is surprisingly smooth and robust for a cheap android tablet, and we actually use one as part of our internal testing suite of devices.
You might find that connecting your Garmin Glo to it is a bit of a pain(requiring mucking about in menus) but since it already has GPS included, that effort might be superfluous.
If you have already grown accustomed to the Apple-y way of doing things then learning the Android operating system might be a bit tedious though...