Bedtime stories, starring your family

Once Upon A Us lets parents create personalized, illustrated, narrated picture books with their kids: describe an idea, pick an art style, and a complete book is generated in minutes. We built it end-to-end — the AI generation pipeline, the mobile app, the subscription business model, and the App Store launch.

Minutes

from idea to illustrated, narrated book

1

character sheet anchors every page render

5

IAP products: subscriptions and credit packs

100%

App Store compliance on first submission scope

From the live App Store listing — onceuponaus.com

The hard problem: characters that stay themselves

Anyone can generate one nice illustration. The hard part of an AI picture book is page seven still looking like page one — same kid, same hair, same outfit. The naive approach (generate each page independently) drifts badly. Once Upon A Us generates a single character reference sheet first, then renders every page in parallel, each one anchored to that sheet. The result: consistent characters, and a whole book generated in roughly the time of a single page — because the pages render concurrently, not sequentially.

What we built

• Generation pipeline. Story text via Gemini with structured JSON output, anchored image generation per page, and text-to-speech narration — orchestrated as a background job with live progress the app polls and displays page by page.
• Monetization. A hybrid model via Apple IAP: a Studio subscription with a free trial, plus consumable credit packs that never expire. Longer books cost more credits — enforced server-side, verified with Apple's App Store Server API.
• Trust and safety. Server-side prompt moderation, in-app content reporting, account deletion, and hosted privacy/terms — the full checklist for an app aimed at families, accepted by App Review.
• Value-first onboarding. New users flip through a finished sample book before ever being asked to sign up — the product sells itself before the paywall appears.

How it's built

React Native (Expo) with TypeScript on the front end; Django on the back end; media on Cloudflare R2; Docker images built in CI and pulled by a small cloud VPS, so production stays quiet during deploys. JavaScript-level fixes ship over-the-air in minutes without waiting on App Review. When AI API keys are absent, the whole pipeline degrades to stubs — so development and CI never burn API quota.