There are also the Celestron Starsense and Meade Starlock. The drawback is that I think these only work with their products, but sound a lot like what you describe.
British Astronomical Association
Supporting amateur astronomers since 1890
Supporting amateur astronomers since 1890
There are also the Celestron Starsense and Meade Starlock. The drawback is that I think these only work with their products, but sound a lot like what you describe.