China Mobile now has 15 million iPhone using customers, despite not yet having an agreement letting it sell the device.
The operator revealed the figure to local media, Penn Olson reported. China Mobile has achieved the milestone even though no iPhone models yet support China Mobile's homegrown TD-SCDMA 3G standard, so handset users are stuck with 2G services.
China Mobile will soon be the only Chinese mobile operator not to officially offer the iPhone, once China Telecom starts selling the iPhone 4S on Friday.
But iPhone 4S owners on China Mobile's network have been experiencing connection problems caused by incompatibility with one of the two frequency bands the operator uses for GSM services.
China Mobile has revealed that Apple is likely to release an OS update specifically for the Chinese market to address these problems, People's Daily reported.
The collaboration between China Mobile and Apple on the connection issue lends weight to expectations that Apple will support TD-LTE with any future iPhones that are LTE compatible.
In October, China Mobile chairman Wang Jianzhou toldReuters that Apple has agreed to support TD-LTE, and that the two companies are negotiating on the details.
Morgan Stanley analysts recently predicted that if Apple works out a deal with China Mobile to bring the iPhone to China Mobile, the world's biggest mobile operator by subscribers, it could result in Apple selling an extra 60 million iPhones by the end of 2013.
The importance of the Chinese market to Apple is underscored by the fact that the $10,000 App Store voucher which the company has just awarded for the 25 billionth app download went to China's Chunli Fu.