Speed Up an Old Phone: Storage, Battery and Update Fixes That Work
Speed up an old phone without losing data: fixes for iPhone and Android lag after updates, from freeing storage to battery checks and a safe factory reset.
Equipe iSerialAtualizado · 5 min de leitura
Neste artigo
An iPhone 13 owner posted on Apple’s community forums this summer that their phone had become badly laggy after updating to iOS 26.6. The top reply pointed out that Apple had said iOS 26.6 would do extra Spotlight indexing in the background to get ready for iOS 27. Around the same time, Galaxy A16 owners on Samsung’s forums were describing crashes, freezing and slowness after One UI 8.
That’s how most slowdowns go. If you want to speed up an old phone, you rarely need a factory reset or a new purchase. Full storage, background work after an update, a tired battery and too many apps competing for memory cause most of it, and you can deal with all four yourself.
Work out what’s slowing it down
Two minutes here tells you which fixes are worth your time.
| What you notice | Likely cause | Start with |
|---|---|---|
| Laggy right after an update | Indexing and background optimisation | A few nights on the charger, then the next patch |
| Slow, and storage bar over about 90% | Not enough free space | Freeing 10–15% of storage |
| Slow, and shuts down at 20–30% | Worn battery | Battery health |
| Budget Android stutters switching apps | RAM Plus on slow storage, bloatware | Virtual RAM and unused apps |
| Animations feel choppy | Visual effects on an older chip | Reduce Motion / Remove animations |
| Warm while you’re not using it | Heavy background work, which also causes throttling | Battery usage by app |
Storage lives in Settings › General › iPhone Storage on an iPhone, Settings › Storage on most Android phones, and Settings › Device care › Storage on a Samsung. In Settings › Battery, an app with unusually heavy background activity is often the same one eating processor time.
Timing helps too. Lag that started right after an update points to indexing. Lag that started after installing an app points to that app. A slow slide over months points to storage, the battery or simply age. Each new OS version adds features designed for newer chips, and older hardware feels it.
On Android, try Safe Mode, which loads only system apps. If the phone is fast there, a third-party app is to blame. Uninstall recent apps one at a time.
Free up storage before anything else
For a lot of people this is the biggest single improvement. When storage runs low, the system has less room for caches and temporary files and everything slows. Keep at least 10–15% free.
- iPhone: in Settings › General › iPhone Storage, follow the recommendations, offload apps you don’t use, and review large attachments.
- Android: use Files by Google › Clean, or Settings › Device care › Storage on a Samsung.
- Move photos and videos to cloud storage or a computer, then empty the “Recently deleted” folders.
- Delete downloaded Netflix, YouTube and Spotify content you’ve already watched or listened to.
Check whether the battery is holding it back
An ageing battery can’t deliver peak power, so phones may limit performance to avoid sudden shutdowns. On an iPhone, open Settings › Battery › Battery Health. If maximum capacity is under about 80%, or iOS says performance management has been applied, a new battery can bring back much of the original speed. Every message on that screen is explained in our battery health and parts history guide.
An iPhone that slowed down after updating
- Wait, with the charger in. Indexing usually takes a few days. Leave the iPhone on power and Wi-Fi overnight two or three times, because iOS does a lot of its background work while charging and idle. Judge it after that, not on day one.
- Install the latest point update from Settings › General › Software Update. First releases (the x.0 versions) often get performance fixes within weeks. Our iOS 27 problems and fixes page tracks what Apple has fixed.
- Turn on Reduce Motion in Settings › Accessibility › Motion, and Reduce Transparency in Settings › Accessibility › Display & Text Size. Older iPhones feel noticeably snappier with both.
- Trim the Home Screen. Live, animated and frequently refreshing widgets cost processing power. Long-press the Home Screen, remove the ones you don’t use, and cut back on Live Activities.
A budget Android that stutters
Start by updating everything. In the Play Store, tap your profile › Manage apps & device and update all. Then check Settings › Software update on a Samsung or Settings › System › Software updates on a Pixel.
Turn off RAM Plus or virtual RAM. Lots of budget phones “extend” RAM by borrowing storage as memory. On a phone with slow storage, that can make things worse. On a Samsung, go to Settings › Device care › Memory › RAM Plus, turn it off or lower it, and restart. Other brands call it Extended RAM or Memory extension.
Get rid of bloatware. In Settings › Apps, sort by size or last used and uninstall what you don’t need. Pre-installed apps that won’t uninstall can often be disabled. Fewer apps, less background activity.
Use Lite apps. Heavy social apps are among the worst offenders on cheap phones. Their lighter versions, or the mobile website, often run much faster. A lighter launcher can help too.
Cut animations. On a Pixel it’s Accessibility › Color and motion › Remove animations; on a Samsung, Accessibility › Visibility enhancements › Reduce animations. If you’re comfortable with Developer options, set the animation scales to 0.5x.
Clear the cache of the worst apps in Settings › Apps › [app] › Storage › Clear cache. Temporary files go. Accounts and data stay.
Habits that keep it quick
Restart once or twice a week to clear memory leaks and stuck processes. Samsung can do it for you with Settings › Device care › Auto optimisation.
And don’t install “cleaner” or “booster” apps. Most don’t help, and many run constantly in the background, which is exactly what you’re trying to stop.
Resetting as a last resort
If it’s still slow after all of the above, a factory reset gives you a clean system. It fixes software clutter, corrupted settings and leftover app data. It won’t fix:
- a worn battery (replace it instead)
- too little RAM or storage for the apps you use
- hardware damage, water exposure for example
- an OS version that is simply too demanding for the chip
A reset deletes everything. Back up first with our backup guide, then follow our guide to factory resetting a phone properly. Afterwards, set the phone up as new and reinstall only the apps you actually use. Restoring a full backup brings the clutter straight back.
If you replace it with a used phone
When a new battery and a clean setup still don’t make the phone usable, a newer second-hand phone is often the best value. Check it before you pay:
- Look at battery health on the phone itself.
- Make sure it isn’t blacklisted or locked.
- Confirm the model and storage match the listing. An Apple full GSX report covers iPhones, and a Samsung Info report covers Galaxy phones.
Your first All-in-one Basic Info check is free:
Perguntas frequentes
Why is my iPhone slow after an update?
iOS re-indexes files and analyses photos in the background after an update, which can cause lag for several days. Charge it overnight on Wi-Fi for a few nights and install any follow-up update.
Does clearing storage speed up a phone?
When storage is nearly full, yes. Keeping about 10–15% free gives the system room for caches and temporary files.
Does a new battery make an old phone faster?
It can. A worn battery may trigger performance limits on iPhones and instability on other phones, and replacing one below about 80% health often brings the speed back.
Should I turn off RAM Plus on Samsung?
On low-end phones with slow storage, turning it off or down can make the phone smoother. Restart after changing it and compare.
Do phone cleaner apps work?
Most don’t, and some run in the background all the time and slow the phone down. Use the built-in storage tools or Files by Google.
Will a factory reset speed up my phone?
It can clear software clutter and corrupted settings, but it erases everything. Back up first and try the other fixes before resetting.
