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Last Tuesday, the USPTO issued US Patent No. 8,046,721 to Apple Inc. for a method of unlocking a hand-held device (it also included two product claims). The "Slide-to-Unlock" method claim is set out in Claim 1 and reads as follows:
1. A method of unlocking a hand-held electronic device, the device including a touch-sensitive display, the method comprising: detecting a contact with the touch-sensitive display at a first predefined location corresponding to an unlock image; continuously moving the unlock image on the touch-sensitive display in accordance with movement of the contact while continuous contact with the touch screen is maintained, wherein the unlock image is a graphical, interactive user-interface object with which a user interacts in order to unlock the device; and unlocking the hand-held electronic device if the moving the unlock image on the touch-sensitive display results in movement of the unlock image from the first predefined location to a predefined unlock region on the touch-sensitive display.
2. The method of claim 1, wherein the moving comprises movement along any desired path.
3. The method of claim 1, wherein the moving comprises movement along a predefined channel from the first predefined location to the predefined unlock region.
4. The method of claim 1, further comprising displaying visual cues to communicate a direction of movement of the unlock image required to unlock the device.
5. The method of claim 4, wherein the visual cues comprise text.
6. The method of claim 4, wherein said visual cues comprise an arrow indicating a general direction of movement.
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So if you hear leaves rustling behind you on this, the most haunted of all nights, it may be Sleepy Hollow, or the ghost of Jack the Ripper, but it could be something arguably far scarier - Apple's next mobile patent lawsuit...
Other Apple v Samsung disputes - here
Bobbing for apples - here
How to make shrunken apple heads (AmeriKat recommended!) - here