Windsor Geek
I've got a 3G dongle and would like to use it with my Android tablet. Is that possible?

If the tablet has a USB socket into which the 3G dongle can be plugged and the appropriate driver software for the Android OS you should be all set. If not it could be tricky to achieve this with the dongle. However there is an app available via the Google Play store called PPP widget which is a no cost app. Results are apparently mixed so without testing this with the specific tablet and dongle it's difficult to predict how it'll pan out.

The article I've posted here describes tethering as a way of getting an internet connection when away from all accessible WiFi signals. That is a viable alternative option in this case. A further option - and arguably the best - is to get a 3G modem that'll work the SIM from the 3G dongle to create your own WiFi hotspot wherever you happen to need it. The article posted here is a review of a good 3G modem/router which is helpfully provided with apps for both IOS and Android. This example is associated with Vodafone but other 3G providers have equivalent products available.