Does not Save the pic to roll – Dash of Color - Black & White, Colorful Photo Editor with Grayscale Effects Review

This app seems great till you try saving your work to Camera roll... Saves it as a black pic ... What's the use of the app and its features if it doesn't save your work for you??? Is the app developer even checking the reviews and doing anything to fix the issue and how did Apple Inc. allow this app in their store without vetting the app and functioning of it?
Review by Wake up Apple Inc on Dash of Color - Black & White, Colorful Photo Editor with Grayscale Effects.