Can you send a link to the tablet you use for cockpit navigation that does not require a mobile contract in the UK

I am being told by retailers I need a mobile contract to use GPS in a tablet , some on this forum say not required

Looking to get a genuine link or model number so I can go and purchase.

Thanks ...

This is a list of my own and my friends equipment to run SD. I installed it and showed them how to use it.

4 ea  Nexus7 (wifi) (5.1.1) with GNS2000 external bluetooth GPS
1 ea  Yoga2 10" (wifi) (5.1.1) with GNS2000 external bluetooth GPS
1 ea  Apple iPad MIni (wifi) with GNS2000 external bluetooth GPS
1 ea Apple iPad (cellular) with XGPS160 external bluetooth GPS

Except for the iPad, we all use 'Bluetooth GPS Provider' app to link the GNS2000 with the Android tablet. The external GPS permits better placement in the cockpit. The aircraft involved are: two high wing Cessnas (177RG and 208) and two Beech Bonanza low-wing. There are less signal drops with the external GPS. The external GPS is placed near the windshield or side window.