There’s a particular kind of annoyance that comes from your phone restarting itself in the middle of something — a text you were typing, a call, a photo you were about to take. It vanishes, the screen goes black, and thirty seconds later you’re staring at your lock screen wondering what just happened. If this is becoming a pattern rather than a one-off, the good news is that it’s usually solvable, and it rarely means your phone is dying.
Most random restarts come down to one of five things: a misbehaving app, a buildup of corrupted system files, a battery that’s starting to wear out, the phone overheating, or, less commonly, an actual hardware fault. The trick is narrowing down which one you’re dealing with, because the fix looks different depending on the cause.
Start Here Before You Panic
Before assuming the worst, run through this short sequence. It resolves the issue for a surprising number of people.
Restart the phone manually first — it sounds almost too simple, but a manual restart clears out temporary glitches that a forced, unplanned restart doesn’t. Then check for pending updates, both for the operating system and your apps, since an outdated app is one of the most common triggers. Take a look at your battery usage in Settings and see if anything is behaving strangely — one app eating far more power than it should is often the smoking gun. If storage is running low, under about 10% free space, clear some out, because a nearly-full phone can become unstable during background tasks. And if none of that helps, try booting into Safe Mode on Android, which temporarily disables third-party apps — if the restarts stop, you’ve found your culprit.
If you’ve already tried all of that and the restarts are still happening, the cause is probably a bit deeper, so let’s go through the possibilities properly.
The Most Likely Culprit: A Problem App
By far the most common cause of random restarts is a single app that’s crashing in a way that takes the whole operating system down with it, rather than just closing on its own. This tends to happen right after installing something new or after an app update, so if you can remember when the restarts started, think back to what you installed or updated around that time.
Safe Mode on Android is the cleanest way to test this — it temporarily shuts off everything except built-in apps, so if the phone behaves normally there, a third-party app is almost certainly responsible. On iPhone, since there’s no direct equivalent, the more practical approach is offloading apps one at a time, starting with anything installed or updated recently, and watching whether the restarts stop.
Corrupted System Files
Sometimes it’s not an app at all — it’s leftover corrupted data sitting in the system cache, often left behind by a software update that didn’t fully complete. This is more common than people realize, especially if the update happened while the phone had low battery or unstable Wi-Fi.
Clearing the cache partition on Android through Recovery Mode, or resetting all settings on an iPhone (which doesn’t erase your data, just preferences and configurations), tends to clear this up. It sounds like a bigger step than it is — neither of these touches your photos, messages, or app data.
Overheating Is More Common Than You’d Think
Phones are built to protect themselves, and one of the ways they do that is by forcing a restart when internal temperatures climb too high. If your phone tends to restart specifically during gaming sessions, while navigating with GPS running, or when it’s charging in direct sunlight, overheating is very likely the explanation rather than anything more serious.
The fix here is almost embarrassingly simple: take the case off (cases trap heat more than people expect), stop charging if it’s plugged in, and let it sit somewhere shaded for ten to fifteen minutes. If the pattern only shows up during specific heavy use, that consistency is itself the confirmation you need.
When It’s the Battery
A battery that’s starting to fail doesn’t always announce itself with obviously short battery life. Sometimes the first sign is instability — the phone restarting because the battery can’t deliver steady power under load, or because it’s misreporting its own charge level, dying suddenly at 30% when it claims to have plenty left.
You can check this directly. On an iPhone, Settings > Battery > Battery Health & Charging will show you a percentage — anything meaningfully below 80% is worth taking seriously. On Android, the exact path varies by manufacturer, but Settings > Battery > Battery usage history showing sudden, unexplained drops is a similar red flag.
A Power Button That’s Not Quite Right
This one’s easy to overlook. If your restarts happen more often when the phone’s been in your pocket or bag, it’s worth checking whether the power button itself feels different than it used to — stickier, looser, slower to spring back. A button that’s getting physically pressed by fabric or pressure inside a bag can trigger restarts that have nothing to do with software at all.
Malware, Though It’s Rarer Than People Assume
This is genuinely uncommon, especially on iPhone, and even on Android it usually only becomes a factor if you’ve installed apps from outside the Play Store. But if the restarts started after installing something from an unfamiliar source, it’s worth running a scan with a reputable security app and checking your installed apps list for anything you don’t recognize.
Storage Running Low
When a phone’s storage gets critically full, background processes — photo backups, automatic updates, cache management — can start behaving erratically, and on some devices this manifests as instability severe enough to cause a restart. Freeing up roughly 10% of total storage usually settles this down.
A Software Update That Didn’t Land Well
If the restarts started right after your phone updated itself, this is very likely your answer, even though manufacturers rarely acknowledge it outright. It happens more than you’d think. Check whether a follow-up patch has been released — often there’s a fix within a week or two. Android phones sometimes allow rolling back to a previous version if the update is causing serious problems; iPhones generally don’t offer that option, so in that case you’re mostly waiting for Apple to release a fix.
And Sometimes, It’s Genuinely Hardware
If you’ve worked through everything above and the restarts are still happening, especially if the phone feels warm even sitting idle, or if you notice any swelling around the battery area, this points toward a hardware issue rather than software. A swollen battery in particular is worth taking seriously as a safety matter, not just an inconvenience — stop using the phone and get it looked at.
Frequently Asked Questions
Will a factory reset fix random restarts?
Often, yes, if the underlying cause is software-related. Back up your data first, since a factory reset wipes everything on the device — but for a stubborn software issue, it’s usually effective.
Can a cracked screen cause my phone to restart?
Not directly in most cases, but if the crack came with internal damage to a connector or affected the battery compartment, that kind of physical damage absolutely can cause instability, restarts included.
Is it normal for a phone to restart once a month?
An occasional, isolated restart — particularly right after an update — isn’t unusual. What’s worth investigating is a pattern: several restarts a week with no obvious trigger.
Does restarting a phone reduce battery life over time?
No. A manual restart is completely safe for the battery and is actually a healthy habit, not something to avoid.