What clearing your phone means and why you might do it
Clearing your phone means removing data from it — either everything (a full factory reset) or just the files and apps you choose. People clear their phones for different reasons: selling or giving away a device, fixing performance problems, removing a virus or malware, or simply starting over with a cleaner setup.
The risk is permanent data loss. Once you delete something, it is usually gone for good, even if you change your mind later. That is why the first step is always backing up the things you want to keep.
Key Takeaways
- Back up your photos, contacts, messages, and app data before clearing anything, because deletion is usually permanent.
- A full factory reset removes everything and returns your phone to its original state, while selective deletion lets you keep what matters.
- On Android, back up through Google Account settings; on iPhone, use iCloud or a computer with iTunes.
- After a factory reset, your phone will ask you to sign in with your Google or Apple account to restore apps and settings.
Back up your data before you start
Backing up means copying your important files to a safe place outside your phone. If something goes wrong during the clearing process, or if you realize you need something later, a backup is your only way to get it back.
On an iPhone, you have two main options. iCloud backup is automatic if you have an Apple account: go to Settings, tap your name at the top, select iCloud, then iCloud Backup, and turn it on. Your photos, messages, contacts, and app data will upload to Apple's servers. Alternatively, you can plug your iPhone into a computer with iTunes or Finder, right-click the device, and choose Back Up — this creates a local copy on your computer instead.
On Android, open Settings, go to Accounts, select your Google Account, tap Account Services, and choose Backup. Turn on Backup by Google One (or Backup, depending on your phone version). This backs up your contacts, calendar, photos, messages, and app data to your Google account. Some Android phones also have a manufacturer backup — Samsung phones, for example, have Samsung Cloud in Settings.
For photos and videos specifically, consider uploading them to Google Photos (Android and iPhone) or Amazon Photos. These services let you store unlimited photos at reduced quality, or pay for full resolution. This way, even if something happens to your phone, your pictures are safe.
Selective deletion: removing apps and files you do not need
You do not have to reset your entire phone to clear it. If you just want to remove clutter, delete apps and files one at a time.
On iPhone, press and hold an app icon on your home screen, tap Remove App, then choose Remove from Home Screen (keeps the app installed but hides it) or Remove App (uninstalls it). To delete photos or videos, open Photos, tap Select in the top right, choose the items you want to remove, and tap Delete. Messages work the same way: swipe left on a conversation and tap Delete.
On Android, press and hold an app icon, tap Uninstall, and confirm. To delete photos, open Google Photos or your phone's gallery app, select the images, and tap Delete or Trash. For messages, open your messaging app, long-press a conversation, and tap Delete.
Clearing your cache — temporary files apps create — can also free up space without losing anything important. On iPhone, go to Settings, select General, tap iPhone Storage, choose an app, and tap Offload App (this removes the app but keeps your data) or Delete App. On Android, go to Settings, select Apps, choose an app, tap Storage, and tap Clear Cache.
Factory reset: removing everything and starting fresh
A factory reset erases all data on your phone and returns it to the state it was in when it left the factory. This is the most thorough way to clear a phone, and it is what you should do before selling or giving away a device.
On iPhone, go to Settings, tap General, select Transfer or Reset, choose Erase All Content and Settings, and enter your passcode. If you have Find My iPhone turned on (which you should), you will need to enter your Apple ID password to confirm. The process takes a few minutes, and your phone will restart several times.
On Android, the steps vary slightly by manufacturer. Generally, go to Settings, select System or About Phone, tap Reset or Reset Options, choose Factory Reset or Erase All Data, and confirm. You may need to enter your PIN or pattern. Some Android phones ask you to remove your Google Account before resetting — if yours does, go to Settings, select Accounts, choose your Google Account, tap Remove Account, and confirm before starting the reset.
After a factory reset, your phone will boot up as if it is brand new. You will be asked to set up your language, connect to Wi-Fi, and sign in with your Google (Android) or Apple (iPhone) account. Once you do, your backed-up apps, contacts, photos, and settings will download automatically.
Removing your accounts before selling or giving away your phone
If you are giving your phone to someone else, a factory reset alone is not enough. You also need to remove your accounts so the new owner cannot access your email, photos, or payment information.
On iPhone, before you reset, go to Settings, tap your name at the top, scroll down, and tap Sign Out. Enter your Apple ID password. This removes your Apple account from the phone. Then go back to Settings, select General, and choose Transfer or Reset to do the factory reset.
On Android, go to Settings, select Accounts, choose each account (Gmail, Samsung, etc.), tap the three-dot menu, and select Remove Account. Confirm the removal. Then go to Settings, select System, and choose Factory Reset.
After the reset, the next person to set up the phone will need their own account. If you skip this step and just reset, they may be locked out by Activation Lock (iPhone) or Factory Reset Protection (Android), which require the original account credentials to proceed.
Fixing performance problems without losing everything
If your phone is slow or crashing, you may not need a full reset. Try these steps first.
Restart your phone: hold the power button, slide to power off, wait 10 seconds, then turn it back on. This clears temporary memory and often fixes lag or freezing. If that does not work, clear your browser cache. On iPhone, go to Settings, select Safari, and tap Clear History and Website Data. On Android, open your browser (Chrome, Firefox, etc.), tap the three-dot menu, select Settings, choose Privacy, and tap Clear Browsing Data.
Uninstall apps you do not use. Apps running in the background consume battery and memory even when you are not using them. Go through your home screen and app drawer, and remove anything you have not opened in months. Check your storage too: on iPhone, go to Settings, select General, tap iPhone Storage, and delete large files or apps. On Android, go to Settings, select Storage, and see what is taking up space.
If your phone is still slow after these steps, a factory reset may help — but only if you suspect malware or a corrupted system file. If the problem is just too many apps and files, clearing selectively will solve it without the hassle of resetting everything.
Securely erasing data so it cannot be recovered
Standard deletion and factory resets do not always make data impossible to recover. Specialized tools can sometimes retrieve deleted files from a phone's storage. If you are selling a phone with sensitive information, you may want extra assurance.
On iPhone, a factory reset is fairly secure because Apple encrypts data by default. Once you erase, the encryption keys are destroyed, making recovery extremely difficult. Do not worry about additional steps unless you work in a field with strict data security rules.
On Android, the level of security depends on your phone model and whether encryption is enabled. Most modern Android phones encrypt data, but older ones may not. If you want to be certain, you can enable encryption before resetting. Go to Settings, select Security, and look for Encryption or Encrypt Phone. This process takes an hour or more and cannot be undone, so only do this if you are certain you want to proceed. Then do the factory reset as normal.
For maximum security, some people physically destroy the storage chip in a phone before recycling it, but this is rarely necessary for personal use. A factory reset followed by a full backup restore on the new owner's account is sufficient for most situations.
Frequently Asked Questions
Can I undo a factory reset?
Not directly — once a factory reset completes, the data is gone from your phone. However, if you backed up beforehand, you can restore from that backup when you set up your phone again. This is why backing up first is so important.
What happens to my apps and subscriptions after I clear my phone?
Apps you purchased or downloaded for free are tied to your account, not your phone. After you restore from backup or sign back into your account, they will download again automatically. Subscriptions (like Netflix or Spotify) are also tied to your account, so you will still have access — you just need to sign in again.
Do I need to remove my SIM card before resetting?
No. A factory reset only erases the phone's internal storage, not the SIM card. Your phone number and carrier information stay on the SIM. You can leave it in during the reset.
How long does a factory reset take?
Usually 5 to 15 minutes, depending on how much data is on your phone and which model you have. Do not turn off your phone or remove the battery during this time — let it complete fully, even if it restarts multiple times.
What if I forget my password before resetting?
On iPhone, you will need your Apple ID password to complete the reset. If you forget it, go to iforgot.apple.com to reset it before you start. On Android, you will need your Google account password. If you forget it, go to accounts.google.com and follow the recovery steps. You cannot reset without these credentials.