Engineering teams of Apple and Google’s joined hands together to create a decentralized contact tracing tool to determine whether they have been exposed to someone with COVID-19. The first phase of the project is an API that public health agencies can integrate into their own apps. The next phase is a system-level contact tracing system that will work across iOS and Android devices on an opt-in basis. If a match is found with another user that has told the system that they have tested positive, you are notified and can take steps to be tested and to self-quarantine. There is zero use of location data, this tool is not about where affected people are but instead whether they have been around other people.