According to Tencent, whose services include instant messaging service QQ, microblogging site Tencent Weibo - which is similar to Twitter - and online games, WeChat has close to 300 million users.

BBC: Tencent

Microblogging tools from Sina and Tencent should be used to identify where there are problems to be corrected.

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Tencent, which is a major player in the Chinese market, offers several internet services, including Tencent Weibo, a Twitter-like microblogging site.

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Sina introduced the microblogging weibo to its online services in 2009 to try to catch up with rival Tencent.

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