I don't usually post about apps, but there are 2 FREE apps that might be of use for some.
1. breethe.com/
apps.apple.com/app/id920161...
play.google.com/store/apps/...
2. dayzz.com/
The company is making this app free during the Coronavirus
apps.apple.com/US/app/id134...
play.google.com/store/apps/...
If you try them, please post about them!