Tap on the bottom left of the sofa, where you'll see a plank on the left.
Change the dark wood colors into the same height like the frames with numbers that is (2 3 1 4). You'll get a electric saw.
Now move to the room which has the TV, on the right hand side below the frame there's a small table. Tap on it and use your electric saw. You'll find your last key.
Now move to the room which has the exit door, tap on the door and use all the keys and you have escaped.
