Apple Corp. submitted a patent application for 'Slide To Unlock' back in 2005. It's a pretty straightforward UI design feature patent - moving your finger across a devices' touch-screen unlocks your device (not specifically 'Phone'). That it's a virtual implementation of mechanical device input locks used years earlier doesn't seem to matter, it's still patentable.
Fast-forward 6 years, and U.S. Patent #7657849 - Unlocking a device by performing gestures on an unlock image - has been granted. This leaves Apple Corp. with sole rights for the process used to unlock a menu by virtually all Android touch-screen smart-devices, as well as a number of non-Android devices. Questions will obviously be asked about the 'obviousness' - one means of striking it down as invalid - of this Patent given the limitations of a device with only touch-screen input; patent lawyers will no doubt argue for years over it and make themselves very rich off the back of it.
It's also worth noting that a Judge in the Netherlands has already invalidated the European version of the same patent under the obviousness rule due to prior art in August, though this didn't prevent the Samsung Galaxy S2 import embargo from going ahead.
One week after posthumous reports stating Steve Jobs vowed to 'destroy Android' surfaced, working with all of Apples resources and till his dying breath to achieve that end, Cupertino has another arrow in its' legal quiver as the Patent Wars continue.
Source 1, 2