Back in June, there were reports of Intel getting orders from Apple for modem chips that would be used for various wireless connectivity which would go into AT&T variants as well as some other versions of the new iPhone 7. Source: Chipworks Chipworks performed a teardown of the iPhone7 which did not stop at just taking the unit apart. The teardown goes even further into the specific chips used in the ‘A1778' iPhone 7 model which they have gotten their hands on. This model is used on AT&T or T-Mobile and other GSM networks. It's not known (but likely) that the CDMA variants...
Source: http://www.gsmarena.com/chip_teardown_of_iphone_7_reveals_intel_modems_and_transceivers_for_some_gsm_models-news-20560.php
