A free program for Android, by Rufus Zhu.
What is it about?
Red Alert is an app for WeChat that allows you to automatically detect and open WeChat messages. It will alert you when a friend sends you a message that contains a red banner, so you can quickly take the appropriate action. It can also be configured to automatically send you a notification when a message with a red banner is received.
How does it work?
Once you have installed the app, it is very simple to set it up. In fact, you only have to do two things:
1) Open WeChat and create a group
2) Install the app and click on the "Set up" button
