4Protect Signal with passcode
Your iPhone might have Touch ID or Face ID protection, but what if it falls into the wrong hands when it’s unlocked. During that period, someone can pretend to be you and use Signal to send untoward messages to your contacts.
That is why Signal comes with a Screen Lock feature that locks the app using your phone’s pin, passphrase, or biometric authentication. Whichever if these you might have activated on the device, you’ll need to use again to get into Signal.
Do note that this won’t work if you don’t have any password protection or biometric authentication enabled on your phone. Signal merely harnesses your device’s authentication means to protect itself.
To enable this on the Signal app, you need to enter the app’s settings and look for the Screen Lock option. If the slider beside it is grey that means it’s disabled and you just need to tap on it once to enable it. You can also set the Screen Lock Timeout, moreover.