Stolen Device Protection closes one of the biggest security holes in the iPhone: the unauthorized stealing of someone's passcode.

We might think of our iPhone unlock code as nothing more than a barrier to prevent people from looking through our photos and messages, but the reality is that anyone with that simple code could turn your life upside down, empty your bank account, access your email, and change your Apple ID password, locking you out of all of your Apple services. But with a few clever changes, Apple is about to put a stop to that altogether.

"Stolen Device Protection is a great initiative to protect access to sensitive features like Apple ID, Wallet, and iCloud Keychain. The extra step of repeating biometric authentication before performing secure actions prevents a thief with knowledge of the iPhone passcode from performing the most critical actions to completely compromise a user's iPhone and Apple ID account. It's also not overly intrusive, as a user likely doesn't need to perform these actions on a regular basis," security consultant Stephen Bondurich told Lifewire via email.

Last year, Joanna Stern and Nicole Nguyen of The Wall Street Journals investigated a major security flaw in iOS devices. Here’s the problem: If a thief has your iPhone’s unlock code, aka your device’s passcode, they can use it to reset your Apple ID passcode. Because your iPhone is considered a trusted device, Apple assumes you’re the one using it.