One of Apple's (AAPL 1.27%) huge competitive advantages is its ecosystem. Thousands of independent software and hardware developers are working hard every day to make great products for iOS devices -- all of which make your phone and tablet (and Apple stock) ever more valuable to you.

Today, Motley Fool analyst Rex Moore reviews one of those products: The LensMag kit from Carson, which acts as a macro lens for your iPhone 5 camera.