Symptoms
- Battery drops several percent per hour with light use
- Battery lasts noticeably less time than it used to
- Phone feels warm even when mostly idle
- One app shows unusually high battery use in settings
Likely causes
- CommonOne app using excess background activitySettings > Battery > Battery usage shows per-app use; a spike from one app points to the culprit.
- CommonDegraded battery health from ageAn older battery holds less charge and drains faster relative to actual use.
- PossibleWeak cell signal forcing the radio to work harderSearching for signal in low-coverage areas burns extra power.
- PossibleSync, location, and background data running constantlyApps syncing or tracking location in the background add up over a day.
- Less commonA recent Android or app update reindexing or optimizing in the backgroundDrain often settles within a day or two after an update.
What to do
- Open Settings > Battery and check usage by app over the last 24 hours.
- Note any app using far more battery than its screen-on time would suggest.
- Check Settings > Battery > Battery health if your device shows it, or use a manufacturer battery care app.
- Restrict background data or battery usage for apps you don't need running constantly (Settings > Apps > [app] > Battery).
- Turn off high-accuracy or always-on location for apps that don't need it.
- Update the app or Android system if an update is available, since drain bugs are often fixed quickly.
- If one app is still the top drainer after updating, uninstall and reinstall it.
- If drain continues with no clear app cause, suspect the battery itself and consider a battery health check.
When to call a pro
If a manufacturer diagnostic shows significantly reduced battery capacity and drain is severe, a battery replacement at a manufacturer store or repair shop is the direct fix.
Safety
Generally low risk
Generally low risk for a careful person. Stop if anything looks different from what this guide describes.