For the record, this is an unofficial Portal game that has been ported to Android and not licensed by Valve. The portal game centers around the player’s ability to move through portals from one end and out the other, just like the original Portal video game.
The build is completely unofficial and has been ported on a Unity Engine. You can find a pre-developed file for this game in this russian forum, but unfortunately there is no telling whether this particular build will be good or not. It’s up to you, if you decide to try it out, but you have been pre-warned. Check out the cool video from the Unity Engine. I can see Valve being completely unhappy about this. If you do decide to install it, let us know how you got on with it. To be honest, I’ve looked through the video and it’s pretty impressive for the early stages of development.