WeChat, the incredible messaging app that does so much more than simply enable people to stay in touch, is the latest to be caught in the cross-fire between the US and China. For domestic users in mainland China, WeChat functionalities include being able to transfer money for goods & services through WeChatPay, play games, order a cab, send video content, attach files, access online gaming, book appointments & create friend groups, ensuring that this is the app that more than one billion people have installed on their phones.