We’ve all been there: that once in a lifetime moment is happening right before your eyes, and your only means of capturing it is with your phone’s camera. By the time you get it out of your pocket, unlock it, get to the homescreen, launch the camera app, and wait for the camera to boot up, the moment is gone. Opportunity lost, and now everyone is mad at you.
As of iOS 5, you can access the camera right from the lockscreen (you don’t even have to unlock it! Don’t worry, though: you can’t access your older photos this way. Your booty pics are safe.)
To quick-jump to the camera: from the lock screen (the screen with the “Slide to unlock” bar), double tap the home button. You’ll see music controls pop up on top, while a camera icon appears directly beside the unlock bar. Tap that, and you’re immediately inside the camera. (Note: this only seems to work on the iPhone and camera-enabled iPod Touches. It’s a no go on iPad.)