Which App Is Draining Your Android Battery?
Short answer
Open Settings → Battery → Battery usage and switch the view to Show full device usage. The number that matters is not the percentage next to each app but the split between screen time and background time — an app using 15% across four hours of screen-on is normal, an app using 15% with two minutes of foreground use is misbehaving. Restrict those under Settings → Apps → [app] → Battery → Restricted. Rapid drain across every app usually means the battery itself is worn.
On this page
Your phone was at 80% at lunchtime and 20% by mid-afternoon, and you barely touched it. Somewhere in the battery statistics is the answer, but the screen that shows them is easy to misread — and the ranked list that looks like the answer usually is not.
The useful information is not which app used the most battery. It is which app used battery it had no reason to use.
Reading the battery screen properly
Open Settings → Battery. What you see next depends on the brand, but every version has the same two views and the default one is the less useful of them.
On a Pixel: Battery usage, then the three-dot menu → Show full device usage.
On Samsung: Settings → Battery → Battery usage, then the three-dot menu → Show system apps for the complete picture.
The default view hides system components and shows only apps. The full view includes Screen, Android OS, Mobile network standby and Cell standby, which is where several common problems actually appear.
The split that matters
For each app, tap into it. You get two figures:
- Screen time or Foreground — battery used while you were looking at it.
- Background — battery used while you were not.
This ratio is the diagnosis.
| Pattern | What it means |
|---|---|
| High usage, high screen time | Normal. You used the app a lot. |
| High usage, near-zero screen time | Problem app. It is running when it should not be. |
| Low usage, high background time | Usually fine — a push connection idling. |
| “Mobile network standby” high | Poor signal. The radio is burning power searching. |
| “Android OS” or “Android System” high | Often a stuck wakelock or a sync loop. |
An app that shows 18% with three hours of screen time is doing exactly what you asked. An app that shows 9% with ninety seconds of foreground time is the one to act on.
The usual culprits
Some patterns recur across almost every phone.
Social and video apps. Instagram, TikTok, YouTube and Facebook are genuinely expensive — continuous video decode plus network plus a bright screen. If they top the list with matching screen time, nothing is wrong.
Location-hungry apps. Anything with a persistent location permission — fitness trackers, delivery apps, weather apps — can run GPS far more often than necessary. Change the permission to Allow only while using the app under Settings → Apps → [app] → Permissions → Location.
Email and sync. An account with a broken password or an unreachable server retries indefinitely. A single stuck corporate email account can cost 15% a day. Remove and re-add the account.
Poor cellular signal. Not an app at all. In a weak-signal area the modem transmits at maximum power continuously. “Mobile network standby” high in the full-device view is the signature. Wi-Fi calling or airplane mode in known dead zones is the fix.
A recently updated app. If drain started on a specific day, check what updated. Buggy releases that hold a wakelock are common and usually fixed within a version or two.
Restricting a problem app
Once identified, go to Settings → Apps → [app] → Battery (or App battery usage on Pixel) and choose:
- Unrestricted — can run freely. For apps you need live notifications from.
- Optimised — the default. Reasonable for most things.
- Restricted — cannot run in the background at all.
Restricted has a real cost. The app’s notifications will arrive late or only when you open it, because the system refuses to wake its process. That is the correct trade for a game or a shopping app and the wrong one for your messaging app. If you restrict something and then wonder why alerts stopped, that is why — delayed notifications covers the reverse problem in full.
Samsung users have an additional lever: Settings → Battery → Background usage limits → Deep sleeping apps. Apps added there never run in the background, which is more aggressive than Restricted.
Checking whether the battery itself is worn
If no single app stands out and everything drains faster than it used to, the cell is probably the problem rather than the software.
Lithium-ion batteries lose capacity with charge cycles. A phone typically retains around 80% of its original capacity after 500 full cycles, which most people reach somewhere in year two.
Signs the battery is degraded rather than the software:
| Symptom | Why it indicates wear |
|---|---|
| Shutdown above 10% charge | Voltage sags below the cutoff under load |
| Drops of 10-20% in one step | Worn cells report charge inaccurately |
| Phone very hot while charging | Increased internal resistance |
| Drain uniform across all apps | No single process is responsible |
| Visible swelling or a lifted screen | Stop using it immediately |
| Two or more years of daily charging | Expected cycle count reached |
Where to find the real numbers
- Pixel (Android 15+) — Settings → Battery → Battery health shows an estimated capacity percentage and cycle count.
- Samsung — Settings → Battery and device care → Diagnostics → Battery
status, which reports Good / Normal / Weak. For the detailed figure, dial
*#0228#to open the service menu and read the voltage and capacity. - Any phone — Accubattery estimates capacity over several charge cycles. Treat its first-week numbers as unreliable; it needs data to calibrate.
A battery reporting under about 80% of design capacity is a replacement candidate. A battery causing shutdowns at 20-30% charge is already failing.
If the battery is visibly swollen — a lifted screen, a bulging back panel, a phone that no longer sits flat — stop charging it and do not puncture it. A damaged lithium cell is a genuine fire risk. Take it to a repair shop.
What not to do
- Do not install a battery saver app. It cannot control other apps without system permissions it does not have, so it kills processes that Android then restarts, at a net energy loss. It also runs constantly itself and usually serves ads.
- Do not kill apps from the Recents screen as a habit. Cold-starting an app costs more energy than leaving it cached. Android’s memory management is better at this than you are.
- Do not factory reset as a first step. It occasionally helps when a rogue sync is stuck, but it is hours of work to test a hypothesis you can test by removing one account.
- Do not trust the percentage immediately after a system update. Android rebuilds app caches and re-indexes for a day or two afterwards, and drain is genuinely higher during that window. Wait 48 hours before investigating.
- Do not assume the screen being top of the list is a fault. On a modern OLED phone at high brightness and 120Hz, the display is usually the single biggest consumer and that is by design.
Quick wins that actually work
If you want results without diagnosis:
- Lower screen brightness and turn off adaptive refresh rate boost.
- Set location permissions to While using the app for everything except maps.
- Turn off Always-on display, which costs 5-10% a day.
- Remove email accounts you no longer use.
- Restrict the three worst background offenders from the battery screen.
- Enable Adaptive Battery if notifications are not critical to you.
Together these typically recover a few hours of real-world runtime on a phone with a healthy cell. On a phone with a worn battery they will not, and that is the clearest signal that replacement rather than tuning is what is needed.