Use ATT iPhone in Hong Kong?

You have to unlock the phone first.

 

You will need to unlock it first. If you are using data then use Smartone cause the signal is better than 3.

Remember to get iPhone cases as a souvenir (woman's market is the cheapest). It's so cheap here!

 

SmarTone-Vodafone (SMV) doesn't sell prepaid sim card with data. It is voice only. Choices of prepaid sim with data in HK are 3, CSL and Peoples. Go for 3 because CSL is too expensive and Peoples is 2G network only (unless you don't care about speed...HK$78/30days).

In terms of stability, SMV is better than 3...but a lot of people switched from 3 to SMV because of slow data and instability...and SMV is now much slower than before (even slower than 3)...but it is still more stable than 3 (especially during peak hours or in Subway)

Get this 3 prepaid sim card :
http://www.three.com.hk/website/appmanager/three/home?_nfpb=true&_pageLabel=P200470391219567710594&lang=eng&pageid=61I001

 

Could you comment a bit more on the CSL prepaid service please?
http://tillschadde.blogspot.com/2010/04/prepaid-data-plan-for-iphone-in.html