Why Planner Reminders Don’t Go Off on Android (and How to Fix It)
Short answer: on Android, a planner reminder that never arrives is almost always caused by one of four things: battery optimization stopping the app in the background, the Alarms & reminders (exact alarm) permission being turned off, the app’s notification channel being muted, or reminders lost after a phone restart. Check them in that order. Most people fix it at step 1 or 2.
1. Turn off battery optimization for the planner
Android and phone makers aggressively pause apps you are not using to save battery. If the planner is paused, its scheduled reminders can be delayed by minutes or hours, or skipped. This is the most common cause, especially on Samsung, Xiaomi, OnePlus, Oppo and Huawei phones.
- Open Settings → Apps and select your planner app.
- Tap Battery (sometimes “App battery usage”).
- Choose Unrestricted instead of Optimized or Restricted.
- On Samsung, also open Settings → Battery → Background usage limits and make sure the app is not in “Sleeping apps” or “Deep sleeping apps”. Add it to “Never sleeping apps” if you want to be sure.
- On Xiaomi/Redmi, enable Autostart for the app and set battery saver to “No restrictions”.
2. Allow “Alarms & reminders”
Since Android 12, apps need a special permission to fire an alarm at an exact minute. Without it, Android may batch the reminder and deliver it late. On Android 14 and newer this permission is off by default for many newly installed apps.
- Open Settings → Apps → Special app access → Alarms & reminders.
- Find your planner and turn it on.
- Reopen the planner so it can reschedule its reminders.
3. Check the notification settings
Sometimes the reminder does fire, but you never see or hear it.
- In Settings → Apps → your planner → Notifications, make sure notifications are allowed. On Android 13+ the app must also have been granted the notification permission.
- Apps split notifications into channels (for example “Task alerts”). Open the channel and check that it is not silenced and that its importance allows sound and pop-up.
- Check Do Not Disturb and any bedtime or focus mode. If reminders matter during those times, add the app as an exception.
- Check the phone is not on silent or vibrate if you expect a sound.
4. Reboots and edited tasks
Android clears all scheduled alarms when the phone restarts. A well-built planner listens for the reboot and schedules everything again; a poorly built one simply stops reminding you until you open it. If reminders only fail after a restart or an update, open the app once to trigger rescheduling, and consider switching apps.
The opposite problem is a reminder for the old time after you edited a task, or a reminder for a task you deleted. That means the app did not cancel the previous alarm. Again, this is an app bug rather than a setting.
Quick checklist
- Battery usage set to Unrestricted, and the app not in any sleeping list.
- Alarms & reminders permission on.
- Notifications allowed, channel not silent, Do Not Disturb exception if needed.
- Open the app once after a restart or update.
- Test it: create a task two minutes from now, lock the phone and wait.
How Daystrip handles reminders
Daystrip schedules each task’s start and end alerts as exact alarms, so they arrive on the minute when the permission is granted. Editing a task cancels its old alert and schedules the new one; deleting a task removes its alert. After your phone restarts, Daystrip restores all upcoming alerts automatically. Repeating tasks (every day, weekdays, weekends or picked days) get the next occurrence scheduled without any subscription. If an alert still does not arrive, the steps above, battery usage first, are where to look.