Touch button in Blueprint, event on release

I’m in the middle of creating a mobile game in Unreal Engine 4 and I need an event on releasing touch.

Basicaly what I’m trying to do: If you touch the whole left side of the screen, a character goes to a position on the left, if you touch the right side, he goes to the right, but when you release, he goes to the middle. I have it working on keyboard, how do I create touchable screen parts on mobile? Should I try to make two big buttons covering the screen sing UMG?

Any advice appreciated, thank you for your time.