interact(target)
  .draggable({
    inertia: true
  })
  .resizable({
    inertia: {
      resistance: 30,
      minSpeed: 200,
      endSpeed: 100
    }
  })

Inertia allows drag and resize actions to continue after the user releases the pointer at a fast enough speed. The required launch speed, end speed and resistance can optionally be configured with the settings below.

If an action ends without inertia but is snapped or restricted with the endOnly option, then the the coordinates are interpolated from the end coords to the snapped/restricted coords.

Options

• resistance is a number greater than zero which sets the rate at which the action slows down. Higher values slow it down more quickly.

• endSpeed is the speed (pixels per second) at which the action is considered to have stopped.

• allowResume is a boolean value which indicates whether the user should be allowed to resume an action while it is in the inertia phase.

• smoothEndDuration is the duration (milliseconds) of the interpolated movement from the actual end coords to the modified coords with endOnly. Set the value to 0 to disable end transitions with endOnly snap/restrict.

When inertia is resumed, the difference between the start and resume coordinates relative to the target’s top left corner, isn’t reflected in the next {action}move events. Instead, an {action}resume event is fired when the pointer goes back down during inertia before regular “{action}move” events are fired again. If you need the difference in coords, you should listen to this event and respond to it as you would to an {action}move event.