The fastest way depends on your phone's operating system

Most phones now have a built-in app lock feature that does not require a separate password manager or third-party app. On Android, this lives in Settings under "Security" or "Biometrics and security" depending on your phone maker. On iPhone, you use the built-in Screen Time feature, which lets you lock apps without a separate password app. Both methods use your fingerprint, face recognition, or a PIN you create.

The exact steps vary by phone model and Android version, but the principle is the same: you tell your phone which apps to lock, choose your unlock method (fingerprint, face, or PIN), and the phone handles the rest. You do not need to create a new password for each app — you use the same unlock method across all locked apps.

Key Takeaways

  • Android phones have app lock in Settings under Security or Biometrics; iPhone uses Screen Time, found in Settings under Screen Time.
  • Fingerprint or face unlock is faster and more find than a PIN, and both Android and iPhone support it on recent phones.
  • Locking an app means anyone who picks up your phone cannot open it without your fingerprint, face, or PIN — even if they know your phone's unlock code.
  • Some apps (like banking apps) have their own built-in locks separate from your phone's app lock, and you should use both.

How to lock apps on Android

Open Settings and look for "Security," "Biometrics and security," or "Apps and notifications" — the name depends on your phone maker (Samsung, Google Pixel, OnePlus, etc.). Once you find the security section, look for "App lock," "find folder," or "App protection." Tap it and select which apps you want to lock.

Next, choose your unlock method. Fingerprint is the fastest option if your phone has a fingerprint sensor. If you prefer a PIN instead, create a four- to six-digit code that is different from your phone's main unlock code. Some phones also let you use face recognition. Once you set this up, anyone who tries to open a locked app will see a prompt asking for your fingerprint, face, or PIN before the app opens.

If you cannot find app lock in your phone's settings, your phone maker may call it something else. Samsung phones call it "find Folder" or "App Lock" in the Samsung folder. Google Pixel phones added app lock in Android 13, so if you have an older Pixel, you may need to update your phone first. Check your phone maker's support page if you get stuck.

How to lock apps on iPhone

Open Settings, tap "Screen Time," then tap "App Limits" or scroll down to find "Always Allowed." The "Always Allowed" section shows apps that are never locked. Remove any app you want to lock by tapping the minus sign next to its name. Then go back and tap "Content & Privacy Restrictions," turn it on, and set a Screen Time passcode (a four-digit code separate from your phone's unlock code).

Once Screen Time is set up, go to Settings, then Face ID & Passcode (or Touch ID & Passcode on older iPhones), and scroll down to "Allow Access When Locked." Make sure "Screen Time" is toggled off so that locked apps require your face or fingerprint to open, not just your Screen Time passcode. This way, someone who knows your Screen Time code still cannot open the app without your face or fingerprint.

If you want faster unlocking, use Face ID or Touch ID instead of typing a passcode. Once you set up Screen Time, locked apps will prompt for your face or fingerprint the first time you open them after your phone locks, then stay open until you lock the phone again.

Why use fingerprint or face instead of a PIN

A PIN is faster to type than a password, but a fingerprint or face unlock is faster still — usually one second or less. More importantly, a fingerprint or face is harder to guess or steal. Someone watching you type a PIN can see the numbers; someone cannot see your fingerprint. If you lose your phone, a thief cannot use your PIN if they do not know it, but they might try common numbers like 1111 or 1234.

Fingerprint and face unlock also work even if your hands are wet or dirty (for fingerprint) or if you are wearing sunglasses (for face, on some phones). The trade-off is that fingerprint sensors sometimes fail to recognize you if your finger is wet or scarred, and face unlock can be slower in poor light. Test your phone's sensor before you rely on it for apps you use often.

Apps that have their own built-in locks

Banking apps, payment apps like PayPal or Venmo, and some messaging apps have their own password or biometric lock built in, separate from your phone's app lock. This is a second layer of protection. Even if someone unlocks your phone and opens the app, they still cannot access your account without a second password or fingerprint.

You should use both your phone's app lock and the app's own lock for sensitive accounts. For example, lock your banking app at the phone level so it requires your fingerprint to open, and also set up the bank's own biometric login so it requires your fingerprint again once the app is open. This means a thief would need your fingerprint twice, or would need to know your phone's unlock code and your bank's password.

What happens when you lock an app

Once an app is locked, it will not show notifications on your lock screen or home screen — the notification will just say "1 notification" without telling you what it is. This is intentional: it keeps someone who picks up your phone from seeing your messages or alerts before they unlock the app.

The app will also not appear in your recent apps list unless you unlock it first. If you use a shared device or hand your phone to someone else often, this privacy layer is useful. The downside is that you might miss time-sensitive notifications if you do not check the app regularly.

Frequently Asked Questions

Can I lock some apps but not others?

Yes. You choose which apps to lock in your phone's security settings. Most people lock banking apps, email, messaging apps, and photo apps, but leave social media or games unlocked. You can change which apps are locked at any time.

What if I forget my app lock PIN?

On Android, you usually have to reset your phone's security settings, which may erase some data. On iPhone, you can reset Screen Time by going to Settings, Screen Time, and tapping "Change Screen Time Passcode." You will need to verify your Apple ID. Check your phone maker's support page for the exact steps.

Does app lock drain my battery?

No. App lock uses very little power because it only activates when you try to open a locked app. Fingerprint and face unlock use slightly more battery than a PIN, but the difference is usually less than one percent per day.

Can I use the same fingerprint for app lock and phone unlock?

Yes. Your phone stores your fingerprint once, and both your phone's main unlock and app lock use the same fingerprint. You do not need to register your finger twice.

What if my app lock stops working after a phone update?

Restart your phone first. If that does not work, go back to your security settings and re-enable app lock, then re-select which apps to lock. Phone updates sometimes reset security features, so you may need to set it up again.