For those unfamiliar, contact tracing is the process in which healthcare officials attempt to trace people who have been in contact with another person who might have an infectious disease. In this case, it would be the COVID-19 virus. In the images, it shows how it relies on Bluetooth to transmit information from one device to another.
When a person confirms with a doctor that they have the infection, the app will ask for their consent to share that information. Once consent has been given, it will alert other users who were in contact with that person that they could also be infected, and that they should seek treatment or self-quarantine for the time-being.
Given how fast the COVID-19 virus is spreading, governments around the world are asking people to stay at home for work and study. While this is not a cure, it will help to lessen the burden on healthcare systems. There is currently no cure for the COVID-19 virus, but a recent report from the WHO has revealed that there are about 70 vaccines currently in development.