For added security, Burner's app for both iOS and Android comes with a Passcode Lock feature with optional TouchID integration.
Activating a Passcode for Burner
For iOS users:
Tap on the gear icon at the top of the screen under your All Numbers inbox.
Tap on Lock Burner
On this screen, tap Passcode
Finally, you'll be taken to the last screen! Where you'll be able to create a 4 digit passcode. Keep in mind that the app will have you enter the passcode twice to verify that the numbers are correct! For Android Users:
To activate PIN Lock feature, tap the lock icon in the top right-hand corner of the Inbox.
You'll be presented with this two-step lock workflow. Tap "Lock" to proceed.
Enter a 4-digit PIN (personal identification number) that you are likely to remember. You'll be asked to enter it twice to confirm.
Then press "Lock" when you're done.
On the next screen, you can enable TouchID on iOS if you want to. If you're not sure how to enable it on your Apple device, visit Apple's Support Center article on TouchID.
Deactivating PIN Lock
Android: To disable the PIN Lock, tap the lock icon in the top right-hand corner of the Inbox.
You have the choice of a temporary unlock or to unlock the app completely.
Revisit the same settings as above! Once you're in the Passcode settings. you can simply select No Passcode.