GearVR: Making player walk forward on pad touch and hold

I can’t figure out or find tutorials explaining how to map the GearVR’s (consumer edition) touch pad to player input/movement in Unreal Engine 4.10.4. Basically as a start I want the player to “walk” in the direction he is looking by touching and holding his finger on the touch pad and to stop moving when lifting his finger.

I have a Game Mode blueprint setup, a Player Blueprint (Character Blueprint) and movement works on keyboard presses. I’ve noticed that there are a couple of possible Input → Touch Input actions under the player blueprint called things like “Assign on Input Touch Begin” and “Assign on Input Touch End” but I’m very new to Unreal Engine and have no idea how these works.

I’m trying to find out, too. When I find out I put the solution here. I’m using Unreal Engine 4.14. Sorry for English, I’m using google translator.