What is a security app for iPhone?

I'm looking for an app that takes a picture when somebody tries to unlock my phone. I heard that they have those but I don't know what it's called.

I think Apple's find my iPhone does that, although I lost my iPod touch 4th gen in November when I messed my Apple ID up and accidentally disabled find my iPhone:/ But I'm pretty sure it has the feature, along with remotely setting a passcode, playing a sound to locate it, displaying a message on the screen, remotely clearing everything (warning, find my iPhone get's disabled when you do this), and I'm not sure but there might be more.

From the Splatypus Army Association,
Coltensplat

While Apple hasn't yet enabled any fully functional anti-virus apps for the iPhone, there are several essential steps every iPhone user should take to make their device as secure as possible. (First and foremost, it's crucial to set the device to auto-lock after a specified period of time, and to require a passcode to unlock it… Read for to details
http://www.esecurityplanet.com/mobile-security/10-helpful-iphone-security-apps.html