That is what happened at Tencent, which has been growing at a torrid pace for much of the past decade. Fearing the development of a disruptive technology that could upend this success, Tencent executives say they encouraged the company's software developers and product managers to search for new ideas.  In late 2010, Allen Zhang, the head of Tencent's research and development center in Guangzhou, organized a team of 10 developers to work on a smartphone messaging app. He was inspired by Kik messenger, which he worried might eventually threaten Tencent's dominant, PC-based QQ instant messenger.  Three months later, Tencent released Weixin. With an elegant and easy-to-use interface, the messaging app attracted 50 million users within a year, and over the next two years reached nearly 300 million users worldwide.  Weixin, technology experts say, has what every Internet company executive dreams about: stickiness. Although Tencent does not track the time that users spend on the service, analysts say it is most likely multiples of other major blogging or social media services.  (Read more: Dr. Doom: We're in a tech bubble)  Analysts say Tencent also has a huge opportunity to make money from the free service. By introducing free mobile games — with virtual items available for purchase — and a payment feature that can be used online or offline, Weixin could soon develop into a profitable business with little or no advertising.  The company is now experimenting with use of Weixin to book taxis, hotels and airline flights, and even to control televisions and home appliances. Last August, a technology analyst at Barclays forecast that Weixin could have 400 million users and nearly $500 million in revenue this year. With investors anticipating such growth, shares of Tencent have soared 94 percent in the past year.  Some Tencent executives even view Weixin as a company savior. Last year, Tencent's chief executive and co-founder, Ma Huateng — known in English as Pony Ma — said during a speech that the power of Weixin was that it was mobile, like a "portable organ" that unlike a PC was always with the user.  If Weixin had been created by another company, Mr. Ma went on, Tencent might have gone into decline. "Looking back," he said, "those two months were a matter of life and death" for the company.
Weixin is China's killer app, a highly addictive social networking tool. In the United States, a similar version is known as WeChat. The NYT reports.