Incognito Mode in Google Chrome prevents your browser from permanently saving your history, cookies, and site data. However, if you leave an Incognito tab open and accidentally hand your unlocked iPhone to a friend, they can simply open the Chrome app and instantly view whatever sensitive webpage you were browsing.
To prevent this exact scenario, Google introduced an additional layer of biometric security. You can configure Chrome to immediately lock all Incognito tabs behind Face ID (or Touch ID on older models) the moment you exit the app.
How to Enable Biometric Incognito Locks
This feature is completely optional and disabled by default.
- Open the Google Chrome app on your iPhone.
- Tap the three-dot menu icon in the bottom-right corner of the screen.
- Scroll across the top row of icons in the pop-up menu and tap on Settings (the gear icon).
- Scroll down and tap on Privacy and Security.
- Locate the toggle switch labeled Lock Incognito tabs when you close Chrome.
- Toggle this switch to the On position.
Your iPhone will immediately prompt you to scan your face (or fingerprint) to verify your identity and confirm the setting change.
How the Lock Works in Practice
Once enabled, the lock operates seamlessly in the background.
If you are browsing a webpage in Incognito Mode and swipe up to return to your iOS home screen, the Chrome app instantly blurs the Incognito session. If someone taps the Chrome icon to reopen the browser, they will not see the webpage. Instead, they will be greeted by a dark grey screen with a padlock icon and a button that says Unlock with Face ID.
If the person holding the phone is not you, they cannot view the tabs. However, it is important to note that they can still navigate away from the locked Incognito screen and view your standard, non-Incognito browser tabs without needing Face ID.