https://www.reuters.com/article/us-health-coronavirus-britain-app/contact-tracing-app-for-covid-19-could-be-rolled-out-in-2-3-weeks-developer-idUSKCN22A1H5 >A contact tracing app designed to let people know if they have been in close contact with someone who tested positive for COVID-19 could be rolled out widely in Britain in two to three weeks, a senior official said on Tuesday.