Best Battery Saver App for Android: Start With Settings

Most people do not need a battery saver app. Android already limits what apps do in the background, and Google’s own documentation for developers says a third-party app cannot improve the power use of an Android device. What an app can do is measure: the health of the battery, the speed of a charger, which app is using the charge.

We read Google’s and Samsung’s help pages and Android’s developer documentation, then went through the listings on Google Play. Seven of the ten apps this article recommended in 2019 have left the store. Of the three that remain, two are battery monitors.

Why a battery saver app cannot do much

Android has had two power-saving features built in since version 6.0. Its developer documentation calls them Doze and App Standby. Doze puts off background processor and network work when the phone has been lying unused, and App Standby holds back the network activity of apps you have not opened lately. Both apply to every app, with nothing for you to switch on.

Many of the old battery savers worked by closing other apps. Android 14 took that away: Google’s notes for developers say that since that version an app can only kill its own background processes. The same passage explains why. Android keeps recently used apps in the background on purpose and removes them itself when it needs the memory. Closing them early makes things worse, because starting an app from nothing takes more power than resuming it.

That page then says plainly that a third-party app cannot improve the memory, power or thermal behaviour of an Android device, and reminds developers of Google Play’s policy on misleading claims. So an app that promises to boost, clean or cool its way to a longer charge is promising something the maker of the system says cannot be done.

The battery saver already on your phone

Battery Saver

Open Settings, tap Battery, then Battery Saver. Google’s help page says that while it is on, the phone switches to Dark theme and limits or turns off background activity, so some apps and features may be delayed. On a Pixel you can have it come on at a battery level you choose. Apps then refresh only when you open them, and location services stop when the screen is off. Pixel 3 and later add Extreme Battery Saver, which pauses most apps.

Adaptive Battery

Adaptive Battery learns which apps you use and lets the ones you rarely open run less while you are not using them. It is on by default. Google’s advice is to leave it on, and it notes that after you set up a phone it can take a few weeks to reach full effect. On a Pixel the switch is under Settings, Battery, Battery Saver, Adaptive Battery.

Settings for each app

Under Settings, Battery, Battery usage, tap View by apps to see what has used the charge. Tap an app, then Allow background usage. Google recommends keeping every app on Optimized. For some apps you can go further and stop background use altogether, which is the fix for a single app that keeps draining the battery.

Samsung Galaxy phones

Samsung’s equivalent is Power saving, under Settings, Battery. Samsung warns that background apps may not update or send notifications while it is on. The same Battery menu has Background usage limits, where the phone can put unused apps to sleep automatically. An app you add to Deep sleeping apps never runs in the background and only works when you open it. Samsung’s battery page lists the rest, including a Battery protection setting that can stop charging before 100% to slow the battery’s ageing.

What stretches a charge

Google’s battery help page lists the settings that use less power. None of them needs an app:

• Let the screen turn off sooner.
• Lower the screen brightness, or let it adjust automatically.
• Turn on Dark theme.
• Turn off keyboard sounds and vibration.
• Restrict apps with high battery use.
• Delete accounts you no longer use.

The same page says heat drains a battery faster and can damage it, and that you should use the charger that came with the phone. For the screen settings, see our guide to screen dimmer apps for Android.

How to check battery health

On a Pixel 8a or later, open Settings, Battery, Battery health. Google shows the status as Normal or Reduced, and Reduced means capacity has fallen below 80%. On the same phones the charge cycle count is under Settings, About phone, Battery information. Google says the Pixel 6a to Pixel 8 Pro do not show a health status.

On a Galaxy phone, open the Samsung Members app, tap Support, start Phone diagnostics and choose Battery status. On other phones, look in the battery settings or on the maker’s support site. If there is nothing, this is the one job where an app earns its place.

Battery apps that measure something

Battery health: AccuBattery and Battery Guru

AccuBattery was on this list in 2019 and is the one we would still install, because it sticks to measuring. Its listing says it measures the battery’s real capacity in mAh and shows how much wear each charging session adds. A charge alarm reminds you to unplug. The Pro upgrade removes the ads and keeps history older than a day.

Battery Guru covers the same ground and adds temperature alarms, a charging history and a monitor for wakelocks, the mechanism apps use to keep a phone awake. Its listing carries a line more battery apps should have: it measures and displays, and does not claim to modify your battery, speed up charging or extend battery life.

Both work from your charging sessions, so the capacity figure is an estimate that builds up over time.

Finding the app that drains: GSam Battery Monitor

Start with Android’s own Battery usage screen. GSam Battery Monitor goes deeper: it ranks what it calls app suckers and lets you sort them by processor use, sensor use and wakelocks. It also estimates time remaining from your past use.

Testing a charger: Ampere

Ampere shows the current going into or out of the battery, so you can plug in two chargers or two cables in turn and see which is faster. Its developer is frank about the limits. The listing says the readings are not exact science, are only good for comparing chargers on the same phone, and that some phones lack the chip the app needs.

No ads: DevCheck and BatteryBot

DevCheck is a hardware information app with a battery section. The listing calls it completely ad-free. The free version shows live temperature, voltage, current and health, and the paid Pro upgrade adds tracking of battery use with the screen on and off. BatteryBot is smaller: an open-source indicator that puts the exact percentage in the status bar and asks for no special permissions.

Battery HD, also from the old list, turns the percentage into hours left for calls, music, video and browsing.

Apps to skip

Skip anything whose listing promises a faster phone or a longer charge from one tap, and anything sold as a cleaner, a booster or a cooler. Android’s documentation, described above, is the reason.

Greenify is a different case. It is still on Google Play, with no ads, and it does something specific: it puts chosen apps into hibernation, using an accessibility service on phones that are not rooted. Its own listing warns that a hibernated app loses its alarms and push messages. Adaptive Battery and Samsung’s sleeping apps now do a similar job inside the system, so we have left it out.

Which one to pick

• The phone does not last the day: no app. Turn on Battery Saver earlier, check Battery usage and restrict the app at the top.
• You want to know if the battery is worn: the Battery health screen on a Pixel 8a or later, Samsung Members on a Galaxy, AccuBattery on anything else.
• Something drains it overnight: Android’s Battery usage screen, then GSam Battery Monitor or Battery Guru for wakelocks.
• Charging seems slow: Ampere, with two cables to compare.
• You want numbers and no ads: DevCheck or BatteryBot.

What happened to the old list

DU Battery Saver, PowerPro, Power Battery, Kaspersky Battery Life, Deep Sleep Battery Saver and Avast Battery Saver no longer turn up in a search of Google Play. The Battery Doctor of 2019 has gone as well. An app from a developer called Anyscanner carries that name today, under a different listing.

AccuBattery and Battery HD are in the table. Greenify is covered above.

Quick answers

Do battery saver apps work?

Not the kind that promise to save power. Google’s documentation for Android developers says a third-party app cannot improve the power use of an Android device. Battery Saver in your settings is part of the system and does work.

Should Adaptive Battery be on or off?

On. Google’s help pages say to keep Adaptive Battery and battery optimisation on for best results.

How do I check battery health on Android?

On a Pixel 8a or later, open Settings, Battery, Battery health. On a Galaxy, use Phone diagnostics in the Samsung Members app. On other phones, AccuBattery or Battery Guru will estimate it from your charging sessions.

What is draining my Android battery?

Open Settings, Battery, Battery usage and tap View by apps. On a Galaxy, open Settings, Battery and tap View details.

Is AccuBattery free?

Yes, with ads. Google Play also shows in-app purchases, and the listing says the Pro upgrade removes the ads.