However, you may well want to add a second barrier to entry for anyone who gets past your lock screen—whether it’s friends or relatives who have borrowed your phone, or someone more sinister who’s managed to work out how to bypass the lock screen. In those situations, a secure folder can protect your most important files—such as photos or documents—from prying eyes, requiring another authentication method such as a PIN code or a recognized fingerprint before it will open up.

Read full article on Wired – Threat Level