Is there a good iOS app that offers a comprehensive set of drawing tools for free without ads?

Sketchbook® is a full-featured drawing application that stands out for providing professional-grade tools at no cost and without advertisements. Its interface includes over 190 customizable brushes, ranging from pencils and markers to textures and blenders, which cater to various artistic styles. For real-world use, hobbyists can sketch on the go, while aspiring artists practice techniques like layering and blending without financial barriers. Reviews indicate that users appreciate the intuitive design, with many noting the absence of ads as a significant advantage for uninterrupted creativity. Features such as predictive stroke smoothing, perspective guides, and extensive layer controls support complex projects, from character design to landscape paintings. However, some limitations exist; for instance, users report occasional glitches with the fill tool, where it might not fully cover intended areas. Additionally, while the free version is robust, advanced features like additional brush packs require a one-time premium purchase. Despite these minor imperfections, the app remains a strong choice for those seeking a reliable, cost-effective solution for digital art, balancing accessibility with depth for both casual and serious creators.