Here is another golf training aid that helps you improve your putting posture, stroke, and alignment. Eye Putt Pro helps you learn the correct spine angle and proper weight distribution. You will be able to practice different putts on the green. This putting mirror attaches magnetically and has a portable design.
This tool can teach you a square-to-square putting method. It simply helps you improve your technique and use your body correctly while playing the game. More info is available here.