I use StraightTalk in NYC with an official unlocked iPhone 4S, because it's less than half the price of AT&T, but dealing with them has been horrendous. If you aren't good with computers, forget about it, ever.<p>They supply their SIM cards with a list of "settings" (APN), but it turns out 1) you can't access them on an unlocked iPhone, and 2) they're both wrong and incomplete anyways. Calling them up, their customer service told me it will never work without jailbreaking my iPhone (which is completely incorrect), and gave me <i>another</i> set of settings to try, which also didn't work.<p>In the end, after much Googling, experimentation, etc. (including the T-Mobile SIM card swap trick), I discovered the following worked:<p>- Download the Apple "iPhone Configuration Utility"<p>- Create a profile with not just correct APN settings (att.mnvo) but also the proxy server and port (66.209.11.33:80), despite the fact that the customer service representative kept insisting it must be left blank<p>- Attach the profile to your phone, and restart it once or twice<p>I've accepted the fact that MMS will simply never work, but most people I know use iMessage anyways, so I don't really mind.<p>The absolute worst part was a couple of weeks ago, when StraightTalk decided to change its proxy from 66.209.11.32 to 66.209.11.33, incrementing the IP address by one. My data didn't work for two days, calling them gave me someone else completely unqualified who insisted that they never need to tell anyone when they change their internal settings, because iPhones detect them and self-update automatically, etc. And that besides, nothing had changed, and a proxy isn't necessary anyways. It was only through trial-and-error that I discovered the new functioning proxy (because it happened to be the same as the MMS one, now, unlike before).<p>So, you will save money, but the experience is horrible. It is ridiculous that Apple doesn't expose APN/MMS/etc. settings on their unlocked phones, and it's ridiculous that StraightTalk can't even provide minimally correct information to their customers on how to get their SIM cards to work.