Snapchat is taking a small step toward actually taking your privacy seriously.

Starting this week, the photo-sharing app will warn you if another app on your phone is saving your pictures. Snapchatters using third-party apps will be forced to change their password. If they refuse, their accounts will be locked.

That matters, because the whole point of Snapchat is that photos have a self-destruct timer. This feature makes Snapchat a favorite for sexting -- sending nude images.

But there's a false sense of privacy, because numerous third-party apps like SaveSnap, SnapGrab and SnapSpy offer users the ability to save incoming photos.

This is why Snapchat isn't really private. The whole system has a massive hole. It's partly the fault of users for downloading the stuff, and Snapchat for taking so long to block them entirely.

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In the past, Snapchat has asked users not to use third-party apps that tap into the company's computer code -- but it hasn't shut them down the way Twitter has. Snapchat said it's asking Apple (AAPL) and Google (GOOG) to block those apps one by one. But they're still around.

On Tuesday, the company issued a statement along with its new policy.

"Repeat offenders may have their accounts locked permanently," said Jill Hazelbaker, a Snapchat spokeswoman.

Keep in mind, though, your buddy can still take a photo of the message with another camera.

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