Crayonbook: AI coloring pages and storybooks for families
A 100% Milannial solo product: parents turn a prompt into printable A4 coloring pages or short storybooks; kids color in the browser; families share links and export print-ready PDFs. Pre-launch — built and dogfooded internally.
Outcomes
- Three equal product loops shipping together: Create (prompt → line art), Color (in-browser canvas), Keep & share (library, public links, PDF)
- 6 art styles, up to 20 pages per storybook, multi-provider AI (Anthropic, Google, OpenAI/Ollama), EN + RO
- Resumable book generation (one image per request) with cleaned flood-fillable line art stored in Postgres
- Kid profiles, optional character consistency, moderation and age levels built in
- EU hosting (Frankfurt on Render); Stripe scaffolded but not enabled (PAYMENTS_ENABLED=false)
Stack
art styles
pages per storybook
AI providers
languages (EN + RO)
Crayonbook is a 100% Milannial solo project - owned, designed, and built end-to-end. It helps parents turn a short prompt into printable A4 coloring pages or short coloring storybooks, lets kids color in the browser, and keeps everything in a personal library with share links and PDF export.
Three loops carry equal weight:
- Create - prompt → line art (single page or multi-page book); style + age controls; kid profiles; optional character consistency.
- Color - in-app canvas with tap-to-fill, brush, eraser, crayon palette, undo/redo; progress saved per page as replayable ops.
- Keep & share - personal library, public share links, PDF export (line art or colored).
Status: pre-launch. The product is built and dogfooded internally; it is not yet publicly launched. Portfolio metrics below are capability numbers only - no user or creation counts until after launch.
Coloring apps usually ship either a static PDF pack or a toy canvas. Crayonbook joins the full loop parents actually need:
- An idea becomes clean, flood-fillable line art (not a photo with a filter).
- Kids can color on a phone or tablet without printing first - then print the colored page later.
- A short storybook can stay character-consistent page to page, with captions and optional read-aloud.
Generation is deliberately resumable: each book page is one serverless request (generate-next), so a six-page book does not blow a function timeout.
Real screenshots from the running local demo (fictional kid names only - Sofia, Matei; no real PII).
Welcome · 01 / 06
A paper-and-crayon landing that draws itself
Public scrollytelling for parents: brand-first hero, live tap-to-fill demo, style strip, and a clear create → color → print story before sign-in.
Create · 02 / 06
Prompt to line art with kid profiles
Parents pick style, age level, language, and which child the page is for. Optional character consistency keeps Max the fox looking like Max across a book.
Viewer · 03 / 06
Resumable generation, page by page
Single pages and multi-page storybooks store per-page prompts and cleaned line art. Books generate one image per request so long jobs stay under serverless limits.
Color · 04 / 06
In-browser coloring that kids can finish later
Tap-to-fill, brush, eraser, and a crayon palette on a working canvas. Fills persist as replayable ops so a page stays recolorable and printable.
Library · 05 / 06
A family library of pages and books
Ready creations, in-progress coloring, and generating books sit in one grid with thumbs from real line-art assets - not placeholders.
Share · 06 / 06
Public share links and print-ready export
A share token opens a public page with the line art (and caption). PDF export covers line art or colored results for A4 printing at home.
Welcome · 01 / 06
A paper-and-crayon landing that draws itself
Public scrollytelling for parents: brand-first hero, live tap-to-fill demo, style strip, and a clear create → color → print story before sign-in.
Create · 02 / 06
Prompt to line art with kid profiles
Parents pick style, age level, language, and which child the page is for. Optional character consistency keeps Max the fox looking like Max across a book.
Viewer · 03 / 06
Resumable generation, page by page
Single pages and multi-page storybooks store per-page prompts and cleaned line art. Books generate one image per request so long jobs stay under serverless limits.
Color · 04 / 06
In-browser coloring that kids can finish later
Tap-to-fill, brush, eraser, and a crayon palette on a working canvas. Fills persist as replayable ops so a page stays recolorable and printable.
Library · 05 / 06
A family library of pages and books
Ready creations, in-progress coloring, and generating books sit in one grid with thumbs from real line-art assets - not placeholders.
Share · 06 / 06
Public share links and print-ready export
A share token opens a public page with the line art (and caption). PDF export covers line art or colored results for A4 printing at home.
- App: Next.js 16 (App Router), React 19, Tailwind v4, Radix UI, Motion
- Data: raw Postgres (
pg) - assets live incb_assetsbytes today (STORAGE_DRIVER=postgres) - Auth: Auth.js (Google), allowlisted today; stable
cb_users.idso public signup is additive - AI: Vercel AI SDK across Anthropic / Google / OpenAI / Ollama for planning; OpenAI + Google image engines for line art; sharp + potrace cleanup
- Print: pdf-lib for A4 export
- i18n: English + Romanian
- Payments: Stripe Checkout scaffold behind
PAYMENTS_ENABLED=false
Hosting is EU (Frankfurt) on Render. Moderation and age levels are first-class, not afterthoughts.