Astro Pixel Processor (APP) is a powerful and popular software tool used in astrophotography for processing and enhancing images of the night sky. Developed by Astro Pixel, a company founded by astronomer and software developer, Marcel Bels, APP has become a go-to solution for professional and amateur astronomers alike. Its advanced algorithms and user-friendly interface make it an essential tool for anyone looking to produce high-quality images of celestial objects.