BGR reports that Apple appears to already be testing a 4G LTE-enabled iPhone with carriers, as evidenced by a special internal carrier test build of iOS carrying a property list file for LTE compatibility.
While we can’t confirm that the upcoming fifth-generation iPhone will be able to support 4G LTE, we can now exclusively confirm that Apple’s carrier partners are testing iPhone models with LTE capability. BGR has obtained evidence of an internal iOS test build from one of Apple’s major carrier partners, and buried in the firmware is a property list (.plist file) for LTE.
The iPhone 5 is expected to support HSPA+ technology for GSM networks, which is being marketed by many carriers as "4G", but carriers are also beginning their rollouts of 4G LTE networks that will bring even faster data speeds. Apple has indicated, however, that it has been reluctant to adopt LTE technology so far due to a lack of appropriate chipsets, with size, power and other issues forcing design compromises that Apple has been unwilling to make. LTE chips suitable for Apple's needs are reportedly set to debut in early 2012.
It should come as no surprise that Apple has been testing LTE technology for the iPhone as it seeks to find the proper time to deploy the functionality. Apple has notably been conservative in adopting the latest cellular technology standards, as evidenced by the original iPhone debuting with only EDGE capabilities when a number of carriers had already begun building out their 3G networks.
