My mum is going to the US on Thursday. The o2 tarrifs on pay monthly ( as she is) are very high when there. She needs to make a few phone calls within the US whilst she is there. My question is. As her phone is locked to the o2 network here will that stop US Sims from working on it if she picks one up when there. It's a Samsung galaxy s4. Thanks.
o2 need to learn a lesson from the 3 network really on the international roaming front.