"WeChat is like WhatsApp, Skype, Instagram and Facebook all in one, with an included payment option and a service that allows for real-time localization and finding friends nearby. In my view, the developers of WeChat have managed to combine the strengths and services of various different apps all in one. This is what I call 'flat to fast' a flat recombination of existing techniques into a very powerful tool."

Kirk Wilson, executive director of the China-British Business Council (China), says almost all British government departments and companies have WeChat official accounts, and almost all senior executives of British companies in China have personal WeChat accounts. The council has more than 900 member companies in China, of which about 70 percent are British and 20 percent are Chinese.

"WeChat is very good for the final consumers in terms of convenience. It is very convenient that you can do all the applications with the wallet, all kinds of things."

Stefan Sack, founder and CEO of HK-based SinEuSyn consulting company, says: "WeChat is so present in Chinese consumers' hands that it is impossible not to use it, as a company.

"Even in business-to-business, the notification of events, products, fairs, etc, is something everyone needs to do now."

He often uses the WeChat Moments service to let others know about work events and social happenings, and to encourage exchanges, he says. However, WeChat's ease of use does have at least one downside, and that is that staff are prone to unwittingly pass on company information that is commercially sensitive, and they need be educated in this regard, he says. Ease of use also means that sometimes the quality of information disseminated is not of the standard that it ideally should be, he says.

Tommy Tang, a project manager with Roland Berger Strategy Consultants, says the app offers various kinds of commercial functions for companies, such as opening WeChat shops. The forwarding of products or information on WeChat Moments can be highly influential with mouth-to-mouth promotion, he says.

The one-time release of an advertisement in the WeChat Moments section can cost millions of yuan. A company in Shanghai has built a third-party platform named Weimob that offers marketing and promotional services to companies on WeChat.

"WeChat's commercialization forms are quite different to those of others and are very flexible for companies," Tang says. "They can do things that are very simple and things that are very complex. The use of WeChat for promotions is a must for companies. It is the most active social media platform in China, and companies can tailor advertising and promotional campaigns on WeChat in accordance with their strengths and needs."

Lyu Ronghui, a researcher with iResearch Consulting Group, says WeChat is one of the most important promotional platforms for companies that want to advertise and to engage in brand building. It is not just a matter of promoting its brands, but more importantly of reaching individuals so that they form positive relationships with brands, and in turn influence buying decisions.

But WeChat is still limited in the way it carries advertisements and promotional activities, she says.

"Companies are certainly keen to promote their goods and services through WeChat a lot more, but that would have an impact on the WeChat user experience, and there is a reluctance by WeChat's owners to allow that to happen. But they do want to find ways to help companies build promotional channels."

The emergence of WeChat has come on the back of the growth of the mobile Internet.

"This has also resulted in changes in the way people socialize and in the way companies promote their products and services. As the mobile Internet has made handheld devices one of the chief tools that people use in dealing with others, including businesses, individuals have begun to demand changes that make the app faster and more fun, and companies have begun to demand closer relationships with consumers and greater efficiency."

Ren Chao, a researcher with the Internet consultancy Analysys International in Beijing, says the important thing for big Internet companies is building an ecosystem, and WeChat is building that based on the mobile Internet. WeChat is likely to be replaced only when handheld devices are supplanted by other kinds of electronic terminals such as glasses and watches, and even unmanned aerial vehicle, he says.

WeChat, like Facebook, needs to pay a lot of attention to the user experience, he says, and as long as it innovates it will continue to be popular.

WeChat's overseas market has expanded greatly since 2011, and it now has more than 200 million users outside China. Nevertheless, China remains by far and away the app's most important sphere of activity.