Got $700? Then you, too, can now have the iPhone 4S on T-Mobile. Apple has begun selling unlocked versions of its latest smartphone on its store, but without the carrier subsidies the handsets will set you back quite a bit.

The 16 GB version of the phone costs $649, the 32 GB version is $749 and the new 64 GB version is $849. The unlocked phones are GSM only, meaning they won’t work with CDMA networks such as Verizon and Sprint, in the United States.

So why would you want an unlocked 4S? World travelers who don’t want to be locked into a plan will be able to switch on the phone’s SIM card and use their own phone on any supported GSM network around the globe. GSM networks are common outside the United States, especially in Europe.

Closer to home, getting an unlocked phone will also let you put the device on T-Mobile, which made it clear that not getting official iPhone support could be a blow to the company. In its last report, T-Mobile reported that its earnings were up 17 percent but named “iPhone 4S launches by competitors” as a possible risk to the company for the fourth quarter.

Related stories:

Apple battery update not working for everyone

Apple updates iOS 5, says it fixed battery drain

Consumer Reports: No antenna-gate for iPhone 4S