9to5Mac reports that the next iPhone -- rumored to be released in September -- has hit final testing stages, with variations of 'N93' and 'N94' models suggesting a possible release on Sprint or T-Mobile.

The next generation iPhone has reached the final testing stage (aka “AP” stage [Thanks, Chronic!]) and is now being carried around by high level Apple and carrier executives [...] While snooping around the iOS 5.0 SDK we located references to “N94″ and “N93.”

Verizon previously let slip that the next iPhone will be a world phone, supporting GSM+CDMA on a single chip and thus cutting out the requirement of Apple producing separate devices for the two carriers. With N93 and N94 variations in play, this further indicates T-Mobile as a likely candidate for carrying the next iPhone which is rumored to be an iPhone 4 packed with the new A5 chip.

In addition, they were told Apple and Verizon are still in negotiations to bring FaceTime over 3G while the next iPhone will keep the same 5MP camera sensor, most-likely due to production delays with Sony.

If true, is that a deal breaker for anyone? And if Apple adds a US carrier, would you rather it be T-Mobile or Sprint?

[9to5Mac]