SketchPop - Photo-to-coloring-page magic + smart coloring for kids

I built SketchPop for my own kids. Watching them get frustrated coloring over the lines in paper coloring books, I noticed two things: kids want to feel successful when they create, and they love coloring things they recognize — like a photo of our cat. So I set out to solve both. The photo-to-line-art engine took the longest — getting clean outlines from real photos at three detail levels (Normal / Fine / Expert) meant experimenting with several edge-detection approaches before landing on one that works on everything from a pet's fur to a toy's hard edges. The smart region-lock was the other big challenge: detecting boundaries, handling anti-aliased edges, and quietly repairing small gaps in line art so paint never "leaks" across the page. The rule I held to throughout: no ads, no accounts, no data leaving the device. Everything — including photo conversion — runs on-device. It works fully offline and supports 11 languages so families everywhere can use it. Hoping it gives other kids the same joy mine had making their first "real" coloring page.