Last week, Boy Genius Report reported that Apple has been testing a 4G LTE-enabled iPhone with carries, and suggested that an “internal iOS test build” was being used for testing. The build was a property list file (.plist) for LTE. BGR says that this is the file Apple was already using to test LTE hardware in the field. LTE is a new type of wireless broadband network that is currently being deployed by Verizon and AT&T. If the next iPhone is 4G LTE compatible, data speeds will be significantly faster.
MacRumors has discovered that the same LTE plist file in the last couple of iOS 5 builds. The LTE.plist file was only found in some of the builds (GSM iPhone 4, CDMA iPad), and it was related to Apple’s internal “Fieldtest” application.
In addition, Engadget posted a photo from a source who claimed that AT&T had installed 4G LTE equipment in a major Apple retail store. Forbes also pointed out that Apple has put out a job listing for field test engineers with specializing in LTE.
Field testing in the wireless industry typically means going outside (into the field) with a new cellphone and measuring its signal strength. It is an integral step that phone makers must take before releasing products to the public.