I did a quick double tap tutorial when someone asked about the best way to go about it. I am not 100% if there is a better way but this is my quick stab at it.
You can find the tutorial here: http://gregmladucky.com/blog/?p=690
This event can be used for anything but in our instance we will make it control the player speed. Currently I have 3 different versions I created, depending on what you need / personal preference you can pick which works best. If anyone has a better solution let me know!
We will create the 3 events which determine if the user has single or double tapped and if the input is still held down. At the end of our event we will apply a speed change to our character movement variable.
Tapping once and holding will increase the player speed to a jog
Tapping twice and holding will increase the player speed to a sprint
Releasing the button will cause the character to walk
The current version will use:
Third Person Template
Uses Unreal Engine 4.8.3
Hope someone finds it useful!