The user has tapped the screen at the same location twice in
quick succession.

Long press

A pointer has remained in contact with the
screen at the same location for a long period of time.

Vertical drag

A pointer has contacted the screen and might begin to
move vertically.

A pointer that is in contact with the screen and
  moving vertically has moved in the vertical direction.

A pointer that was previously in contact with the screen
  and moving vertically is no longer in contact with the
  screen and was moving at a specific velocity when it
  stopped contacting the screen.

Horizontal drag

A pointer has contacted the screen and might begin to
move horizontally.

A pointer that is in contact with the screen and
moving horizontally has moved in the horizontal direction.