In addition, Jego provides free in-app text messaging along with other standard features, such as push-to-talk voice messages, photo sharing, video calling, and a multimedia-sharing function.

In the Chinese market, VoIP calling on Jego from China - if people sign up with a Chinese phone number - to a Chinese landline or mobile phone is not available. This is because Chinese authorities forbid VoIP calls. Therefore, domestic users can only use the messaging and Jego-to-Jego calling services.

Skype's pay-as-you-go calls to China cost around $0.026 per minute (including taxes) in addition to a $0.049 connection fee. Jego will cost $0.022 per minute.

Meanwhile, Jego offers unlimited calling to the Chinese mainland for $15.99 a month or to Hong Kong for $11.79 a month.

Xiang Ligang, a Beijing-based telecom expert, said that the revenue contributed by Jego is going to be limited, because the new business is still "a small one".

"We see Jego as a creative application which will increase customers' loyalty and extend China Mobile's global reach. However, it's unlikely to have a big influence on the carrier's financial performance," Xiang said.

Like many other telecom operators worldwide, China Mobile faces declining growth rates in terms of net profit, largely due to strong challenges from Internet companies such as Tencent's Wechat service, which attracted more than 300 million users in two years and has hit China Mobile's voice and messaging business.

Rumors are circulating that China Mobile plans to revive its Fetion service to combat Wechat. Jego, at the same time, may impose some pressure on Wechat since it also provides similar video calling and messaging services.