I have a 2013 Audi A1 that has the comms pack needed for satnav but I never bothered with paying for the satellite navigation on sd card as it was around £500.
If I buy a card on ebay – something like this, will it work?

I think so. As long as the satnav option is there in the MMI menu.

Wife bought A1 s-line that has facility for sat nav but I think from what I have read is that would still need activated at dealers so will cost almost as much.

^^^ being a cynic/reaslist there is no way Audi would allow it to be so easy to bypass their £500 option. You could see if the dealer will do a special aftermarket price. Personally I think mobile phone sat nav is better now due to live traffic via “social network” and app data sharing.

If it’s anything like the VW satnav, Google Maps Navigation will be waaaaaay better.
Or virtually any other navigation app on a smartphone.

I have tomotom on my iphone. It’s ok but when you’re in a city or coming off a motorway with a few exits close together and someone calls, it’s a pain in the arse as it reverts t being a phone and drops the sat nav. I drive a SQ5 quite often and the Audi sat nav is great. Having it solely on the phone is a pain in the arse.

^^^ being a cynic/reaslist there is no way Audi would allow it to be so easy

^^^ being a cynic/realist, even if it works it’ll probably be shit.