Three-dimensional gestures

1. A method comprising, by a computing device:

identifying a gesture made by a user of the computing device with respect to one or more surfaces of the computing device, the gesture comprising a single trajectory in three dimensions including:

an earlier portion of the single trajectory in a first direction along at least one of the surfaces, the earlier portion comprising a first series of points touching the at least one of the surfaces; and

immediately following the earlier portion of the single trajectory, a later portion of the single trajectory in a second direction, the later portion comprising a second series of points distant from the surfaces, wherein the second direction comprises a deflection from the first direction that follows through on the earlier portion of the single trajectory;

determining a user input based at least in part on a speed of the gesture along the earlier portion of the single trajectory and a speed of the gesture along the later portion of the single trajectory; and

executing one or more actions based on the user input.

2. The method of claim 1 , wherein the gesture is identified using a proximity sensor, camera, or touch sensor of the computing device.

3. The method of claim 1 , wherein the earlier portion is detected using a first sensor of the computing device and wherein the later portion is detected using a second sensor of the computing device.

4. The method of claim 1 , wherein:

the gesture comprises a pulling gesture on and then away from one of the surfaces at a first location of the one of the surfaces; and

the actions comprise:

selecting a user interface (UI) object within a display of the computing device at a first point within the display corresponding to the first location; and

adjusting a user-controllable parameter of an application on the computing device indicated by the UI object based on a distance of an end point of the pulling gesture away from the one of the surfaces.

5. The method of claim 4 , wherein the user-controllable parameter is a speaker volume or a display brightness.

6. The method of claim 1 , wherein the gesture comprises:

a pinching gesture on one of the surfaces at a first location of the one of the surfaces;

a pulling gesture away from the one of the surfaces at the first location;

a movement distant from and across the one of the surfaces toward a second location of the one of the surfaces; and

a dropping gesture on the one of the surfaces at the second location.

7. The method of claim 6 , wherein the actions comprise dragging and dropping a user interface (UI) object within a display of the computing device from a first point within the display corresponding to the first location to a second point within the display corresponding to the second location.

8. The method of claim 6 , wherein the first point is within a first window of a first application on the computing device and the second point is within a second window of a second application on the computing device.

9. The method of claim 1 , wherein:

the gesture is a fly-away gesture; and

the actions comprise:

selecting a scrollable user interface (UI) object at or near a starting point of the fly-away gesture; and

scrolling the scrollable UI object at a speed based at least in part on a velocity of the fly-away gesture.

10. One or more computer-readable non-transitory storage media embodying software that is operable when executed to:

identify a gesture made by a user of a computing device with respect to one or more surfaces of the computing device, the gesture comprising a single trajectory in three dimensions including:

an earlier portion of the single trajectory in a first direction along at least one of the surfaces, the earlier portion comprising a first series of points touching the at least one of the surfaces; and

immediately following the earlier portion of the single trajectory, a later portion of the single trajectory in a second direction, the later portion comprising a second series of points distant from the surfaces, wherein the second direction comprises a deflection from the first direction that follows through on the earlier portion of the single trajectory;

determining a user input based at least in part on a speed of the gesture along the earlier portion of the single trajectory and a speed of the gesture along the later portion of the single trajectory; and

execute one or more actions based on the user input.

11. The media of claim 10 , wherein the gesture is identified using a proximity sensor, camera, or touch sensor of the computing device.

12. The media of claim 10 , wherein the earlier portion is detected using a first sensor of the computing device and wherein the later portion is detected using a second sensor of the computing device.

13. The media of claim 10 , wherein:

the gesture comprises a pulling gesture on and then away from one of the surfaces at a first location of the one of the surfaces; and

the actions comprise:

selecting a user interface (UI) object within a display of the computing device at a first point within the display corresponding to the first location; and

adjusting a user-controllable parameter of an application on the computing device indicated by the UI object based on a distance of an end point of the pulling gesture away from the one of the surfaces.

14. The media of claim 10 , wherein the gesture comprises:

a pinching gesture on one of the surfaces at a first location of the one of the surfaces;

a pulling gesture away from the one of the surfaces at the first location;

a movement distant from and across the one of the surfaces toward a second location of the one of the surfaces; and

a dropping gesture on the one of the surfaces at the second location.

15. The media of claim 14 , wherein the actions comprise dragging and dropping a user interface (UI) object within a display of the computing device from a first point within the display corresponding to the first location to a second point within the display corresponding to the second location.

16. The media of claim 14 , wherein the first point is within a first window of a first application on the computing device and the second point is within a second window of a second application on the computing device.

17. The media of claim 10 , wherein:

the gesture is a fly-away gesture; and

the actions comprise:

selecting a scrollable user interface (UI) object at or near a starting point of the fly-away gesture; and

scrolling the scrollable UI object at a speed based at least in part on a velocity of the fly-away gesture.

18. A device comprising:

one or more processors; and

one or more computer-readable non-transitory storage media coupled to the processors and embodying software that is operable when executed by the processors to:

identify a gesture made by a user of the device with respect to one or more surfaces of the device, the gesture comprising a single trajectory in three dimensions including:

an earlier portion of the single trajectory in a first direction along at least one of the surfaces, the earlier portion comprising a first series of points touching the at least one of the surfaces; and

immediately following the earlier portion of the single trajectory, a later portion of the single trajectory in a second direction, the later portion comprising a second series of points distant from the surfaces, wherein the second direction comprises a deflection from the first direction that follows through on the earlier portion of the single trajectory;

determining a user input based at least in part on a speed of the gesture along the earlier portion of the single trajectory and a speed of the gesture along the later portion of the single trajectory; and

execute one or more actions based on the user input.

19. The device of claim 18 , wherein the gesture is identified using a proximity sensor, camera, or touch sensor of the device.

20. The device of claim 18 , wherein the earlier portion is detected using a first sensor of the device and wherein the later portion is detected using a second sensor of the device.