Web Vampire

Shake to Undo (for Mac OS X)

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However, Apple missed an obvious location for improvement. Although Lion provides many touch gestures that can be activated with the trackpad, it completely ignores the potential ability to use the laptop itself as a gesture device. When both commands and text input are mapped to the keyboard, as is currently the case, the keyboard loses the design focus of being a single-purpose device. When the user has to take additional time to switch to a different input method in order to perform commands, his or her mind will be entirely focused on the task at hand by the time the gesture is performed.

Therefore, I have fixed a small portion of this mistake, by implementing the “Shake to Undo” gesture from iOS. Once the application is running, simply shake your laptop to activate undo. To prevent accidental activation of the undo gesture, there is an optional confirmation overlay, similar in style to the undo overlay on iOS.