The development team tell us about this tool:
Hexels is a creative suite for grid-based painting, animation, and design. The Hexels canvas is a paintable grid of geometric shapes that lets artists create complex designs with the stroke of a brush. It is a new kind of vector workflow, a friendly playground for the beginning artist, and a versatile tool in the hands of a professional.
The price now is the $24.50 and you can read and download it from official website.