The Chinese social messaging app WeChat has just launched a new feature that tracks where users are.
Dubbed WeChat Heat Map, the feature takes location information from smartphones and superimposes the data onto maps, allowing users to see areas of high population density.
Areas with lots of people are marked as red, whereas areas with less people are marked as green.
The principle behind the app is that people will be able to identify and avoid very busy areas.
There are concerns, however, that the data could be misused by the Chinese government to spy on people's whereabouts and crack down on public protests.
An unexpected influx of people in one area could allow the government to infer a protest is taking place and send a mass WeChat message telling people to avoid the area.
WeChat is the most popular social messaging app in China, with a staggering 600 million monthly active users. Â
