BEIJING, May 15 -- Mobile Internet is becoming a lucrative business in China, with improving telecom infrastructures a main contributor, according to a report released on Thursday.

Total revenue in the mobile Internet sector reached 108.3 billion yuan (17.8 billion U.S. dollars) in 2013, said the China Internet Development Report 2014, jointly issued by the Internet Society of China (ISC) and the China Internet Network Information Center.

China has more than 500 million cellphone-based Internet users and high-end subscribers used an average 1.6 Gb of data every month last year, according to the report.

"Chinese Internet users are shifting from desktop to mobile devices," said Shi Xiansheng, vice secretary-general of the ISC.

Shi attributed the expansion of the mobile Internet business to the improvement of the country's underlying Internet facilities.

As of the end of the third quarter last year, 130 million households had access to optical-fiber-based broadband Internet, and 3G mobile Internet had covered all townships.

Along with the development of mobile Internet business, smartphones and wearable devices, including watches, also saw rapid growth.

Last year, smartphone shipments grew by 64.1 percent to 318 million units. Wearable device shipments topped five million units in 2013 and is expected to reach 40 million units by 2015.