Apple Inc plans to hire a manager with knowledge of the third- and fourth-generation networks used by China Mobile Ltd, evidence it's moving toward agreement for the world's largest carrier by users to offer the iPhone.

The carrier engineering manager position, based in Beijing, will "support and drive the carrier approval of mobile phones," Apple said in an advertisement on its Chinese website.

China Mobile has 63 percent of the 1.2 billion wireless subscribers in the world's biggest smartphone market, while Apple has distribution agreements only with the nation's two smaller operators - China Unicom (Hong Kong) Ltd and China Telecom Corp. Apple is near a deal with China Mobile to distribute the iPhone and is preparing to ship devices to the carrier, a person familiar with the talks said last month.

"This role will be responsible for the overall management of the technical interface to all carriers in the Greater China region," Apple said in the ad. "This includes obtaining approvals for all Apple hardware and software, supporting carriers with new technology trials, managing carrier reported technical issues, tracking carrier road maps and supporting senior level engineering meetings."

Carolyn Wu, a Beijing-based Apple spokeswoman, didn't immediately return calls or an e-mailed request for comment on the status of talks with China Mobile and the job posting.

Among the key qualifications for the role are in-depth knowledge and experience with wireless systems including TD-SCDMA and TD-LTE, the ad said. Those are the 3G and 4G standards used by China Mobile. TD-SCDMA is a domestic 3G standard not deployed by any carrier besides China Mobile.

The posting also states a requirement for experience with WCDMA and CDMA, the technologies used by China Unicom and China Telecom, respectively.

Apple's Chief Executive Officer Tim Cook is looking to add a new pool of customers as the company faces slowing sales and profit growth. The Cupertino, California-based company is also grappling with competition from Samsung Electronics Co and makers of lower-cost smartphones.

Cook has visited China at least twice this year and has said the country will overtake the United States as its largest market.