How do I speed up a slow phone?
What actually makes a phone feel slow, in order — storage, background apps, updates and battery health — and what to do about each.
- Difficulty
- beginner
- Time
- 30 min
- Read
- 2 min
Short answer
Free up storage first, since a nearly-full phone slows noticeably. Restart it, check for pending updates, and look at battery health — on older iPhones especially, a degraded battery triggers performance throttling that a battery replacement completely reverses.
Phones slow down for a small number of identifiable reasons, and 'it's old' is usually the least accurate one. Full storage, a degraded battery and pending updates account for most cases, and all three are fixable without replacing the device.
Step by step
- Restart the phone properly.Most phones are never restarted. It clears accumulated background state and genuinely helps.
- Check free storage and get it above about 10–15% of capacity.A nearly-full phone slows markedly. This is the single most common cause. See the storage guide.
- Install any pending operating system and app updates.A phone perpetually mid-update is a phone perpetually busy, and updates often include performance fixes.
- Check battery health.iPhone: Settings → Battery → Battery Health. A degraded battery can trigger deliberate performance throttling to prevent shutdowns.
- Replace the battery if health is low rather than replacing the phone.It costs a fraction as much and often restores the phone completely.
- Uninstall apps you don't use, particularly ones that run in the background.Social, delivery and shopping apps are the usual background consumers.
- Reduce visual effects if your phone offers it.Reduce Motion on iOS, animation scale on Android. It makes an older phone feel noticeably more responsive.
- Clear caches on the largest apps by offloading and reinstalling them.It keeps your account and settings while clearing accumulated cached data.
- Consider a factory reset as a last resort, after a verified backup.It clears years of accumulated state. Only after you've confirmed a backup exists and works.
Tips
- Don't force-close apps routinely — relaunching from cold uses more resources than leaving them suspended.
- Cheap 'phone cleaner' and 'booster' apps do essentially nothing the operating system doesn't already do, and add background load and adverts.
- A phone that gets hot and slow together is thermally throttling. Take it out of a case and out of direct sun.
- Older phones often run better after a few days following a major update, once background indexing finishes.
Common mistakes
- Assuming the phone is simply too old — Storage and battery health explain most slowdowns, and both are fixable far more cheaply than a new phone.
- Installing a cleaner or booster app — They mostly duplicate built-in functions while adding their own background load.
- Force-closing apps constantly — It costs more resources than it saves on both major platforms.
- Factory resetting without a verified backup — It's irreversible. Confirm the backup date and size first.
Questions people ask
Does a degraded battery really slow a phone?
On iPhones, yes — iOS reduces peak performance on significantly degraded batteries to prevent unexpected shutdowns, and this is disclosed in Battery Health settings. Replacing the battery removes the throttling.
Do cleaner apps help?
Generally not. Both iOS and Android manage memory and storage themselves. Cleaner apps mostly duplicate built-in features while adding their own background activity.