on 05-05-2011 08:48
Yes, no problem using giffgaff in either an unlocked phone or one that is locked to parent network O2.
Click the button above to order a normal SIM with £5 bonus credit when you activate with a £10 topup.
iPHONE 4 - Click Here and fill out the order form. I will send you a microSIM with £5 bonus credit by First Class Post.
on 05-05-2011 08:58
Yes you can use a giffgaff sim in a O2 locked phone or any unlocked Phone, you also use O2 Topup vouchers if you can't get hold of a gifgaff one
I'd have a look around for a giffgaff one though, the O2 ones tend to take some getting onto the system, so it can take a while to get it to work