Bit offtopic; For me it shows more, to western apps, how you build an app that always works... with wechat I can do sync and async voice calls, chat and photo sending with any connection, even if it is very slow or intermittend. No western app I have tried, including the actual phone app, does that as well as wechat. I can call, on 2g crappy China Mobile to colleagues in the EU where Skype and Whatsapp will not even…
Are you sure this is not due to the effects of both 1) the GFW and 2) the atrocious traffic shaping Chinese ISPs apply to international connections?
Not sure about Skype, but Whatsapp always works for me even down to 2G, outside of China.