Is an iphone 3gs capable of upgrading to 4g?

Hi redlion35,

Thanks for using Apple Support Communities.

Unfortunately, the iPhone 3GS is not capable of utilizing 4G data connection. You can, however, upgrade to one of Apple's newer devices, such as the iPhone 4s, which is capable of 4G, includes Siri, and uses iOS 7. Or, you can even purchase the iPhone 5s or 5c, providing your provider serves it.

Best wishes,

-Marcus

A clarification: The 4S is only capable for the pseudo 4G that T-Mobile USA and AT&T call HSPA+ in the US. It will not do 4G LTE, you have to have one of the iPhone 5 models for that.