An analysis of the usage of COVID-19 contact tracing apps in 25 US states and DC finds that only 13 have enough usage to benefit from exposure notification (Betsy Ladyzhets/MIT Technology Review)

Betsy Ladyzhets / MIT Technology Review:
An analysis of the usage of COVID-19 contact tracing apps in 25 US states and DC finds that only 13 have enough usage to benefit from exposure notification  —  A year ago, engineers built apps to track potential virus exposure.  Our research shows the impact has been mixed—but there's still potential.