Google Maps updates shows color coded Covid-19 rates by US county when available
or districts in other countries

https://www.cnbc.com/2020/09/23/google-maps-covid-19-layer-shows-coronavirus-outbreaks-near-you.html

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Once you get the update, you’ll be able to use the new feature by doing this:

Open Google Maps.
Tap the layers button, which looks like a square on top of another square.
Choose the “Covid-19 Info” layer.
Now you’ll see a map of cases around the world, color-coded by severity.

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