Contact tracing apps for covid-19 e.g. in Germany still have to apply to current data protection laws and may not be used to track individuals.
The German "Corona Warn App" has been installed more than 5 million times in short time. https://play.google.com/store/apps/details?id=de.rki.coronawarnapp
Many mobile devices had been updated to iOS 13.6 and Android 6 versions in order to support the required new API implemented by Apple and Google:
I found information that a lot of US states and countries are implementing apps using the same API.
So please support iOS 13.6 and Android 6 (latest Google Play Services) to the very next possible date.