Unni and Gunni is the story of two friends who want more color in their life and therefore paints their house in the colors of the rainbow.
Its aim is, in addition to being a fun story, to teach kids about colors. The app is enriched with voice narration and lively music.
Two of the books in this series were actually released as apps (created using TapBookAuthor.com) before being released as physical books. Cool!