A phone that suddenly feels sluggish is usually suffering from one of a handful of fixable problems: storage that is almost full, an update that hasn’t finished settling in, apps running in the background, heat, or a worn battery. Work through the checks below in order — most people find the culprit in the first three or four steps, without losing any data.
The short version
- Restart first — it clears stuck processes and is free to try.
- Keep at least a few gigabytes of storage free; a nearly full phone slows down noticeably.
- Install pending updates, then give the phone a day to finish background indexing.
- Heat and a worn battery can both make a phone deliberately slow itself down.
- Back up before trying a factory reset — it’s the last step, not the first.
1. Restart the phone (properly)
It sounds too simple, but a full restart closes apps and system processes that have stopped behaving and frees up memory. Many people go weeks without ever turning their phone fully off.
- iPhone: press and hold the side button and either volume button until the power-off slider appears, slide it, wait 30 seconds, then hold the side button to turn it back on.
- Android: on most phones, hold the power button (on some Samsung models, the side key plus volume down) and choose Restart.
If the phone feels fine for a day and then slows again, something is building up — keep going down this list.
2. Free up storage space
When internal storage is nearly full, the phone has less room for temporary files, caches and updates, and everything gets slower. It is one of the most common reasons a phone starts to feel old.
- iPhone: open Settings > General > iPhone Storage. You’ll see what is taking up space and suggestions such as offloading apps you rarely use.
- Android: open Settings and search for Storage. Samsung phones also group this under Device care.
The usual space hogs are videos, downloaded streaming episodes, messaging app media (group chats can quietly hold gigabytes of photos and videos) and apps you installed once and forgot. Before deleting photos or videos, make sure they’re safely backed up to the cloud or a computer — our guide on how to back up your phone walks through it.
3. Update the software — then be patient
Updates often include performance and bug fixes, and apps that are badly out of date can misbehave on newer system versions.
- iPhone: Settings > General > Software Update.
- Android: open Settings and search for Software update or System update.
Update your apps through the App Store or Google Play as well. One thing to know: right after a major update, many phones feel slower and run warmer for a day or so while they re-index photos, messages and search data in the background. Leave the phone on Wi-Fi and plugged in overnight, and it usually settles down.
4. Find the app that’s dragging things down
Sometimes one app is the problem — a game, a social app or a browser with dozens of tabs open. Clues include the phone getting slow only after you use a certain app, or battery draining faster than usual.
- Check battery usage by app (in Settings, search for Battery). An app using a surprising share of battery is often also using a lot of processing power.
- Close browser tabs you no longer need, and clear browsing data if the browser itself feels sluggish.
- Delete or reinstall apps that crash, freeze or misbehave.
- Limit background activity: on iPhone, Settings > General > Background App Refresh lets you switch it off for apps that don’t need it. On Android, the battery settings for each app let you restrict background use.
Live wallpapers, lots of home-screen widgets and heavy animations also use resources. On an older phone, trimming them back can make a visible difference.
5. Watch out for heat
Phones protect themselves from overheating by reducing performance. If yours feels hot, it will slow down until it cools off. Common causes are gaming or video calls while charging, using navigation in a car with the phone in direct sun, or a thick case trapping heat during heavy use.
Let a hot phone cool somewhere shaded — never in a fridge or freezer, as sudden temperature changes can cause condensation inside. If your phone gets hot while doing very little, that’s worth having checked, because it can point to a battery or hardware fault.
6. Check the battery
As lithium-ion batteries age, they can’t always deliver the power the processor asks for during demanding moments. To prevent unexpected shutdowns, some phones manage performance when the battery is worn — Apple explains this in its support article on iPhone battery and performance.
Signs that the battery is part of the problem include the phone slowing down most when the charge is low, shutting off unexpectedly, or the battery percentage jumping around. Our guide on how to check your phone’s battery health shows where to look on iPhone and Android. If the battery is worn, a battery replacement can bring back much of the phone’s everyday responsiveness.
Also check you haven’t left a power-saving mode switched on. Low Power Mode on iPhone and power saving modes on Android deliberately reduce performance to stretch battery life — useful in a pinch, but they make the phone feel slower.
7. Factory reset as a last resort
If none of the above helps, a factory reset can clear out years of accumulated settings, leftover files and software glitches. It also erases everything on the phone, so:
- Make a full backup and confirm it finished.
- Know your Apple Account or Google Account password — you’ll need it to set the phone up again.
- Write down any two-factor authentication apps you use and make sure you can move them to the restored phone.
- Reset from Settings (search for Reset or Erase all content and settings), then restore from your backup.
Some people prefer setting the phone up as new and reinstalling only the apps they actually use, which is often the cleanest result.
If your phone is slow and also showing pop-ups, apps you didn’t install, or unusual data use, don’t enter passwords or payment details on it until you’ve removed the unknown apps and updated the software.
When slowness points to a hardware problem
Software fixes won’t help if the phone is slow because of a physical issue. Signs to watch for include freezing combined with a swollen or lifting screen, random restarts, the phone getting hot without use, or problems that started right after a drop or water exposure. A swollen battery in particular should be dealt with promptly rather than ignored.
It’s also fair to accept that very old phones eventually stop getting updates and struggle with modern apps. If yours no longer receives security updates, it may be time to think about a replacement — but try the steps above first, because many “too old” phones simply need storage cleared and a fresh battery.
Need a hand in Downtown Vancouver?
If you’ve worked through these checks and your phone is still crawling, bring it to the MyChoice Mobile Repair kiosk on Granville Street in Downtown Vancouver and we’ll take a look. We help with software problems, battery replacements and other repairs for iPhone, Samsung and other major brands. We’re open every day from 9 AM to midnight — call (236) 785-8300 to check your model, or ask for a quote online.
Need a hand with your phone?
MyChoice Mobile Repair is a kiosk at 798 Granville St in Downtown Vancouver. Call us, message us or send a quote request.
