WeChat is a Chinese social messaging app that allows users to message friends, play games, use tools and find new opportunities for social networking and entertainment. It was created by Tencent, one of China's largest internet companies known for QQ. WeChat is free to use with in-app purchases and can work across iOS, Android, Windows Phone, Symbian and BlackBerry devices. By 2015, WeChat had over 549 million users worldwide, especially numerous users in China, and offers features like messaging, photo sharing, games, location-based functions and social media integration.