Petalica Paint is an AI-powered tool that offers automatic colorization for uploaded sketch images. Users can easily add color hints to influence the colorization process and choose from different colorization styles like "tanpopo," "satsuki," and "canna." The tool also features a sketch simplification tool for refining strokes in sketches. With the ability to simplify and refine, Petalica Paint provides a seamless experience for adding vibrant colors to artwork.