I've only recently got an iPhone and I'm pretty clueless, so please bear with me. We have an iPhone4 and an iPhone4s, both purchased in Hong Kong and our current service is through 3 (Hong Kong). We will be in Ireland for a week and want to be able to make calls to local number and access the internet.
What kind of sim card do I need? Where can I buy it (we arrive in Dublin in 2 days)? How much do they cost? Do I just take out my Hong Kong sim & insert the Irish sim? Any need to activate the card or will it be fully functional once it put it in?
And what happens if someone calls or texts my Hong Kong number, once I switch out my Hong Kong sim card for the Irish sim card? Can they leave a voicemail msg, which I can retrieve once I put the Hong Kong sim back in?