A slow phone doesn’t always mean it’s time to buy a new one. “Slow” can look like apps taking forever to open, a typing delay, scrolling that stutters, random freezes, or a phone that runs hot even when you’re doing simple stuff.
This step-by-step checklist works for both iPhone and Android. Start with quick wins first, then move to deeper fixes only if the lag is still there. After each step, test performance so you know what actually helped.
Start with quick wins that fix most slow phones in 10 minutes
Run these in order, and check speed after each one:
- Restart your phone: It clears temporary memory and stops stuck processes. After reboot, open your slowest app and test scrolling.
- Update the operating system: On iPhone, go to Settings, General, Software Update. On Android, go to Settings, System, System update (wording varies). Updates often fix bugs that cause lag.
- Update apps: Use the App Store or Google Play. A single outdated app can drag the whole phone down.
- Force close heavy apps: If a game or social app is chewing up resources, close it and re-open it fresh.
- Turn down extras: Fewer widgets, no live wallpapers, and less constant location use can make a real difference.
- Try one “control” test: Open the camera, take a photo, then switch apps. If that feels smoother, you’re on the right track.
For more Android-specific speed checks, see CNET’s guide on speeding up an Android phone.
Restart, then update your phone and apps (yes, in that order)
A restart is like clearing a crowded desk. It dumps short-term clutter, ends runaway background tasks, and gives your system a clean start.
Then update your phone, then your apps. If you update without restarting first, you might keep old glitches running in the background. Update when you can use Wi-Fi and keep the phone charging, since big downloads and installs can heat things up.
Stop background drain: close heavy apps, limit background refresh, turn off extras
Background activity can make a good phone feel like it’s trudging through mud.
On iPhone, check Background App Refresh (Settings, General). Set it to Off, or Wi-Fi only if you want a middle option. On Android, open Settings, Apps, pick a problem app, then restrict background use (labels vary by brand).
Also switch off what you don’t use: Bluetooth, constant location access, and extra widgets.
Check storage and memory, low space is a common hidden reason for lag
Phones need breathing room to stay quick. When storage is nearly full, the system struggles to cache files, update apps, and manage photos and messages smoothly. A good target is 10 to 20% free space.
Start by deleting junk first, then big items. The safest order is: downloads, duplicate photos, old videos, then unused apps. Don’t forget to empty trash or “Recently Deleted” albums, because those files often still take space.
Find what is eating space, then delete the right things
Open Settings, then Storage (iPhone: Settings, General, iPhone Storage). Look for the biggest culprits: videos, photo bursts, offline maps, large chat attachments, and apps you forgot you installed.
If you need a broader checklist of common causes, Asurion has a helpful explainer on why phones get slow.
Clear app cache (Android) and lighten heavy apps (iPhone and Android)
On Android, many apps let you Clear cache (Settings, Apps, Storage). This can remove bloated temporary files without wiping everything.
On iPhone, cache controls are limited. If one app is the clear problem, delete and reinstall it, or remove offline downloads inside the app (music, podcasts, video). Don’t clear app data unless you’re sure you know your login.
If it is still slow, look for deeper causes like battery health, bad apps, or overheating
Photo by Kelvin Valerio
Battery health and heat can force your phone to slow down
Old batteries and high heat can trigger performance throttling. On iPhone, check Settings, Battery, Battery Health. A maximum capacity under about 80% is a common point where slowdowns show up.
On Android, battery health tools vary, but check the Battery section or device care features if your phone has them. If your phone is hot, stop gaming while charging, avoid direct sun, and remove the case during charging.
Find the problem app, scan for malware, then do a clean reset only if needed
If lag starts right after opening one app, that’s your suspect. Uninstall recent or sketchy downloads first.
Android has Safe Mode (steps vary) to help confirm a third-party app is the issue. On Android, run Google Play Protect scans. On iPhone, avoid unknown configuration profiles and suspicious “security” apps.
If nothing works, factory reset is the last step. Back up first, then reinstall only essentials so you don’t bring the problem back.
Wrap-up: keep your phone fast
Troubleshoot in this order: restart, update, reduce background activity, free up storage, then check battery health and heat. If the lag persists, remove the problem app, scan for malware, and reset only as a last resort.
After each step, run a simple benchmark: open the camera, switch apps, type a message, and scroll a long page. A weekly restart and a monthly storage check can prevent most slowdowns.