ND Spot On is a tool for calculating the correct shutter speed when using an ND (Neutral Density) filter on your camera. It is a great tool for long exposure photography.

Use your camera's built-in focus and exposure functionality to focus and determine shutter speed without the ND filter Then put the camera in manual focus mode to lock focus, and put the ND filter in place. On the app's main screen, select the original shutter speed and correct ND filter, and the app will automatically calculate the shutter speed with ND filter.

The purchased version of the app includes timer and reminder (both optional) functionality to make your life a lot easier.

The app supports full support for Windows Phone themes.