Can I use a foreign SIM card in my unlocked iPhone 4s?

Question

I Bought a second hand iphone 4s which was on Vodafone, then was unlocked for me by Vodafone to use on T-Mobile in the UK. I am moving to Germany in 2 weeks and want to know if I can use my unlocked iPhone with a German SIM card as my main phone? I don't want to have to buy another iPhone! Any help gratefully received!

Answer 1

For what it's worth - I travelled to the US for a one year period and I lived in California. The reply above is correct in stating that AT&T or T-Mobile are your only options.
To be honest, all you need is voice calls that aren't roaming as WiFi is pretty freely available - at least it was wherever we went.
You could just get a PAYG Sim card from one of the above providers - it was relatively inexpensive for us to use for a year so it should be perfectly adequate for you to use for three weeks.
Yes - there won't be data over Edge or 3G but as I said, WiFi is readily available.
The only issue will be converting an ordinary PAYG Sim into a Micro Sim for your iPhone 4. There are lots of videos showing how easy it is to cut one down - I guess you just want to make sure that it doesn't get stuck in the phone!
The other simpler option would be to leave your UK SIM in place and just turn off data roaming so you can only use WiFi. Then go and buy yourself a cheap PAYG phone from a Target or Walmart or similar. T-Mobile charged us $25 per PAYG SIM from their store whereas we realised we could get the same SIM with a cheap Nokia handset for $20 from the supermarket.
That way, you only need to make sure that you don't use your UK number for calls etc as US roaming isn't cheap.
Hope this helps.