How to Speed Up a Slow or Laggy Android Phone

Check your free storage. Open Settings > Storage (on Samsung: Settings > Battery and device care > Storage). A nearly full phone is the single most common reason for lag, and the easiest to fix.

Check whether the phone is up to date. Go to Settings > System > System update (Samsung: Settings > Software update) and install anything waiting. Updates often include performance fixes, and a half-finished one in the background can itself cause stutter.

And the boring tip that works more often than it should: restart the phone. Phones left on for weeks accumulate stuck background processes; a reboot clears them in about a minute. If the lag only started today, try this first.

Android needs empty space to work in: it uses spare storage for temporary files, app updates, and shuffling data around. When free space drops below roughly 10 percent of the total, or under about 1 GB, the phone slows down noticeably. Aim to keep at least 10 to 15 percent free. On a 128 GB phone that means leaving 13 to 19 GB open.

Where the space usually goes, easiest wins first:

1. Photos and videos. A few minutes of 4K video can be a gigabyte. If you use Google Photos, turn on backup, then on a Pixel let the phone remove copies already safely in the cloud via Settings > Storage > Free up space. A related feature, Smart Storage in the Files by Google app, can delete copies already backed up to Google Photos automatically: Google says it removes backed-up photos once they have been saved for 60 days, or sooner if your free space drops below about 25 percent, as set out on its Files by Google help page. Switch it on in the Files by Google app under Settings.
2. The Downloads folder and old screenshots. These pile up invisibly. The Files by Google app (pre-installed on Pixel, easy to add on any phone) has a Clean tab that surfaces junk files, duplicates, old screenshots, large files, and downloads, and deletes them in a couple of taps.
3. Apps you have not opened in months (covered in the next section).

For a fuller walkthrough of clearing space in your Google account, see our guide on how to free up Google storage on Android. A good file manager app also makes the largest files easy to spot, and a capable gallery app can group duplicates and screenshots for you.

Cache is temporary data an app keeps so it loads faster next time, like saved thumbnails or a partly downloaded feed. Normally that helps. But when one app's cache gets corrupted or bloated, that app turns sluggish or starts misbehaving. Clearing it is a safe, targeted fix: it does not log you out, delete your messages, or remove the app, as Google notes in its Android storage help. The app just rebuilds the cache as you use it.

The key word is targeted: clear the cache of the one app giving you trouble, not everything at once.

1. Open Settings > Apps > See all apps and tap the misbehaving app. (Shortcut: press and hold the app's icon on your home screen, then tap the small i info button.)
2. Tap Storage & cache (on Samsung it is just Storage).
3. Tap Clear cache.

Notice the second button right beside it, Clear storage or Clear data. That one is heavier: it wipes the app back to a fresh install, logs you out, and erases its local settings. Use it only if clearing the cache did not help and you are ready to sign in again. For example, if your bank app keeps freezing, Clear cache first; if it is still broken after a restart, then Clear storage and log back in.

Do not hunt for a button to clear every cache at once; there isn't one on modern Android, and that is fine. Wiping all caches just makes every app slow for a while as they rebuild.

Apps left running in the background sip battery and memory. Android manages this well on its own, but a few habits help on an older or lower-memory phone.

Restrict the heavy ones. In Settings > Apps, social media, store apps, and anything with a constant live feed tend to be hungriest. For an app you rarely use, set its battery usage to Restricted under App battery usage (on Samsung: Settings > Apps > [app] > Battery).

Let Android sleep apps you have forgotten. Android has a built-in feature, app hibernation, that if you have not opened an app in a few months (roughly 90 days) automatically pauses it: it revokes the app's permissions, stops its notifications, and clears its temporary files. It is on by default and worth leaving on. Samsung adds its own list under Settings > Battery and device care > Background usage limits > Sleeping apps, where you can park apps you want kept out of the background.

Skip the urge to force-close everything. Swiping every app out of the recents view all day does not speed things up. Android reloads those apps from scratch when you reopen them, which uses more power, not less. Reserve force-stopping for a single app that has clearly frozen.

Bloatware is the pre-installed apps you never asked for, often from the phone maker or a carrier. Some you can uninstall; others are baked in and can only be disabled, which stops them running and hides them from your app drawer. Both help. To remove or disable one:

1. Open Settings > Apps > See all apps and tap the app.
2. If the Uninstall button is available (not greyed out), tap it. Done.
3. If there is no Uninstall, tap Disable instead. You will see a warning that disabling built-in apps may cause errors in other apps. For ordinary user-facing apps (a duplicate browser, a promotional shopping app, a game you will never play) this is safe. Tap Disable to confirm.

One firm rule: do not disable anything with "Android," "System," "Google Play," or a framework label in the name, and skip anything you do not recognize. Disabling a core system component can stop other apps working or, rarely, leave the phone unable to boot. If unsure, leave it alone.

Samsung phones ship with more of these than a Pixel does, and the same Disable path works on One UI. A few Samsung apps such as Bixby offer neither Uninstall nor Disable in Settings; removing those needs a computer and the Android Debug Bridge tool, which is more involved than most people need. Disabling the obvious extras is plenty.

This is my favourite, because it is free, reversible, and the effect is immediate. Android plays a small animation every time a window opens, closes, or switches. Speeding those up makes the whole phone feel snappier even though the hardware has not changed; you are not removing features, just shortening the transitions.

The setting lives in Developer Options, hidden until you switch it on:

1. Go to Settings > About phone and find Build number (on Samsung: Settings > About phone > Software information > Build number).
2. Tap Build number seven times. It will count down and then say "You are now a developer." You may be asked for your PIN.
3. Go back to Settings > System > Developer options (Samsung: it appears near the bottom of the main Settings list).
4. Scroll to these three settings and change each from 1x to 0.5x: Window animation scale, Transition animation scale, and Animator duration scale.

At 0.5x the animations run twice as fast and the phone feels noticeably quicker. You can set them to Animation off for instant transitions, though that can feel abrupt; 0.5x is the sweet spot for most people. Despite the word "scale," these control speed, not size. To undo it, set all three back to 1x; nothing else in Developer Options needs touching.

Search the Play Store for "speed booster" or "RAM cleaner" and you will find dozens of apps promising to make your phone fast. Skip them all.

These apps claim to free up RAM (the phone's short-term working memory) by closing background apps. But Android is designed to keep recently used apps in spare RAM precisely so they reopen instantly. Empty RAM does you no good; it is wasted capacity. When a booster forcibly clears it, the phone just reloads those apps next time you need them, which uses more battery and can make multitasking slower, not faster. So at best these apps do nothing useful.

At worst they are dangerous. Security researchers and Google have repeatedly found that many "cleaner," "booster," and "battery doctor" apps are stuffed with intrusive ads, harvest your data, or carry malware; Trend Micro documented optimizer apps that quietly committed ad fraud and pulled down malware. Many also push fake "your phone is infected, clean now" pop-ups to scare you into installing more junk. Ignore those; they are not coming from Android.

The honest version of what those apps pretend to do is already built in, free and safe: Files by Google for clearing junk, the storage tools above, and on Samsung the built-in Device care. If you do want a third-party tool for tidying files, stick to well-reviewed, transparent options. Our roundups of cleaner apps and battery saver apps flag which are worth it, and a reputable antivirus app is a far better use of a slot than a memory booster.

Samsung's One UI bundles a useful maintenance hub. Open Settings > Battery and device care and tap Optimize now for a quick sweep: it closes background apps, clears some memory, deletes unnecessary files, and checks for malware. It is the legitimate, built-in version of a "booster," and Samsung describes it in its Device care support article. Running it occasionally does no harm.

You may also spot RAM Plus under Battery and device care > Memory. This borrows a chunk of your storage to act as extra, slower memory. It sounds like a speed feature, but on phones with 8 GB or more of real RAM (most recent Galaxy models) the benefit is usually negligible and can even be slightly negative, because storage is far slower than real memory. If your phone is recent and has plenty of RAM, leave RAM Plus off or at its lowest setting. This is one of the few cases where doing less is better.

If you have worked through everything above and the phone is still slow, a factory reset is the heavy-hitter. It wipes the phone back to how it left the shop, clearing years of leftover files and misbehaving apps, and often restores an older phone to near-new speed. But it erases everything on the device, so it is genuinely a last resort, and Google itself advises trying other fixes first.

Do it properly so you lose nothing:

1. Back up first. Go to Settings > Google > Backup, run a backup, and turn on Back up other device data so app data, texts, and call history are included. Check that your photos are in Google Photos and important files are in Drive or on a computer.
2. Know your Google account and password. After a reset the phone will ask you to sign in to the same Google account before it lets you back in (a theft-protection feature). Confirm the password now, or you risk being locked out.
3. Charge to at least 70 percent and stay on Wi-Fi. A reset and the restore that follows can take up to an hour.
4. Then go to Settings > System > Reset options > Erase all data (factory reset) (Samsung: Settings > General management > Reset > Factory data reset) and follow the prompts.

When the phone restarts, sign in and choose to restore your backup. One caution: if the phone is years old and still slow after a reset, the limit is likely ageing hardware, especially a tired battery, and no software step will fully fix that.