Screenshots of the next iOS version 5.1 pre-GM have leaked and show some minor changes in the works for Apple's next iPhone firmware update. One of the notable changes highlighted by Blog do iPhone is a lock screen camera button that never disappears. Instead of clicking the home button twice to bring up the camera button, the process is simplified.
When the iPhone is locked, to take a photo quickly with iOS 5.1 you can just swipe the camera button up. This saves the step of having to double click the home button then tap the camera button. Apple added the lock screen camera button to provide quick access to the photo and video app, while protecting photo albums and the camera roll until the device is fully unlocked with a passcode.