WeChat is a mobile text and voice messaging communication service developed by Tencent in China, first released in January 2011. It is one of the largest standalone messaging apps by monthly active users.
WeChat provides text messaging, hold-to-talk voice messaging, broadcast (one-to-many) messaging, video conferencing, video games, sharing of photographs and videos, and location sharing. It can exchange contacts with people nearby via Bluetooth, as well as providing various features for contacting people at random if desired (if these are open to it), next to integration with social networking services such as those run by Facebook and Tencent QQ. Photographs may also be embellished with filters and captions, and a machine translation service is available.
The official account of Wechat:
Here is a small video to show you how to use Wechat:
And there is an essay that talking about Wechat in more function from my blog.