What the red dot means
The red dot on an app icon is the notification dot. It means the app has one or more unread notifications. It first appeared on Android 8.0 Oreo (Google Support).
Long pressing the icon can show a short preview on some launchers. Opening the app or clearing its notification removes the dot.
Not the same as privacy indicators
The notification dot is different from the indicator in the status bar. Privacy indicators show camera, mic or location access on Android 12 and later (Android Developers).
Do not confuse these two features. One shows unread alerts. The other shows active access.
Turn off notification dots
On stock Android, go to Settings, then Notifications, then toggle "Notification dots on app icon" off (Google Support).
On Samsung One UI, go to Settings, then Notifications, then Advanced settings, then toggle "App icon badges" off.
These toggles are global. Per app notifications can stay on even if dots are off.
Quick fixes
Clear a single dot by opening the app or swiping its notification from the shade.
If dots persist, check per app notification settings. If a dot appears in the status bar, check privacy indicators for camera, mic or location access.
Device notes
Paths may vary on Xiaomi MIUI, OnePlus OxygenOS, Oppo ColorOS, vivo FuntouchOS or Tecno HiOS.
Some launchers use numbered badges instead of dots. Not all skins expose the same labels.
More Android fixes
For more troubleshooting, see Android problems and fixes.

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