With the evolution of Internet usage, privacy has become increasingly important for users across all platforms. People often resort to private browsing to keep their internet activity away from prying eyes. On Apple devices, Safari offers a private browsing feature that doesn’t save your browsing history, autofill information, or search records. While private browsing in Safari is convenient, it could potentially expose private information to someone who gains access to your device. As of my last knowledge update in March 2023, there isn’t a feature provided by Safari on iPhone, iPad, or Mac to lock private browsing tabs directly. However, you can use some workarounds to secure your private information.

On an iPhone and iPad:

1. Use Screen Time – Go to ‘Settings’ > ‘Screen Time’ and tap ‘Turn On Screen Time.’ Set up a passcode and then go to ‘Content & Privacy Restrictions.’ Here you can restrict access to Safari entirely or password-protect certain features.

2. Close Private Tabs – Remember to close your private tabs after you finish browsing. Although this doesn’t lock them, it prevents others from seeing your activity if they get access to your device.

3. Use Guided Access – You can also enable Guided Access in ‘Settings’ under ‘Accessibility,’ which lets you restrict your device to a single app and control which features are available.

On a Mac:

1. Create a Managed User Account – Go to ‘System Preferences,’ then ‘Users & Groups.’ Click the lock and enter your administrator password. Then click the ‘+’ icon and choose ‘Managed with Parental Controls.’ Using this new account for private browsing will allow you to set restrictions similar to Screen Time on iOS.

2. Use Third-party Applications – There are several third-party applications available that can provide additional security for your web browsing by requiring a password to access the app or particular content within it.

3. Keep Your Device Locked – Ensure that you always lock your screen when stepping away from your Mac by setting a password in the ‘Security & Privacy’ preferences.

Remember, updates happen frequently, and future versions of Safari may include more robust privacy features such as tab locking or user profiles that could offer this functionality natively. It’s always good practice to keep your operating systems up-to-date and regularly check for new features that enhance security and privacy.