The apps would alert people if they have come in close contact with a person who tested positive for COVID-19. Health officials say its a way to find potential new infections and to start reopening parts of society.
Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, says "If we have the capability of isolating and contact tracing in a highly effective and efficient way than the numbers will stay low."
Health experts say it's also about making people feel comfortable as they go out.
Disney Executive Chairman and Chairman of the Board Bob Iger has said as they look to reopen the parks this is something that could be considered.
"We're going to need some mass testing and some form of contact tracing as well so that we can identify people who have been exposed who had the virus and it may be of harm to others," says Iger.
Apple and Google are working on the interface that could be used by developers in public health agencies around the world. They say participation would be voluntary, but some are skeptical.
Privacy attorney Michael Cohen says "that raises a lot of issues with respects to privacy. The fact that this information is recorded that may have impact on how people may decide to use it or not."
Gov. Gavin Newsom announced the state is trying to get 10,000 tracers - people who would be able to process all the information that is collected.
"The history of TB, measles, the health departments throughout the state of California have been running testing, tracking and tracing protocols for sometime," says Newsom.
Experts say the apps work if they are used by as many people as possible. If it's connected to a database the information could be used forever.
"The other question is where is all this being stored and what is the possibility of this information being hacked?" says Cohen.
Several lawmakers say this could be a huge data privacy issue and are calling for strict limits on what contact-tracing data can be collected and shared.