Countdown widget not updating on Android?
Short answer: most stuck widgets are blocked by battery optimization. Exclude the countdown app from battery optimization, remove the widget and add it again. Reviewers also report widgets that "show only a dot" or numbers that shrink: re-adding fixes most of those too.
1. Turn off battery optimization for the app
Settings → Apps → (your countdown app) → Battery → Unrestricted (or "Don't optimize"). On Samsung, also remove it from Sleeping apps.
2. Remove and re-add the widget
Long-press the widget → Remove. Then long-press the home screen → Widgets → add it again and resize. This resets a broken layout after a launcher or app update.
3. Check date and time
Settings → System → Date & time → Set automatically. A wrong time zone can make the number change at the wrong hour.
4. Restart once
After an update or restore, a restart reschedules widget alarms.
Doing it with Nearday
Nearday's widget shows your next day and updates at midnight. Tap › to flip to the next event, tap the card to open it. Events are counted by calendar day, so the widget and the app always show the same number.
FAQ
Why is my countdown widget stuck on yesterday?
Battery optimization often blocks the midnight update. Exclude the app from battery optimization and re-add the widget.
My widget shows a dot or tiny numbers. What now?
Remove the widget and add it again, then resize it. Launcher updates sometimes break the layout.
Does the widget need the app to be open?
No. A well-built widget updates itself at midnight without opening the app.