How 4 Engineers Built Sora for Android in 28 Days Using Codex

When Sora launched on iOS, demand exploded. The Android team had just a prototype and a ticking clock: millions of pre-registered users were waiting. Instead of throwing bodies at the problem, a lean team of four engineers used Codex to ship the production Android app in just 28 days. They consumed about 5 billion tokens from an early version of GPT‑5.1‑Codex—the same tool available to all developers. The result? A 99.9% crash-free rate, an app that hit #1 on the Play Store, and over a million videos generated in the first 24 hours. The team treated Codex like a newly hired senior engineer: it handled the heavy lifting, but humans still had to guide architecture, strategy, and user behavior. The key insight? Adding more people slows you down; but giving a small, sharp team superpowers accelerates everything. Why it matters: This case study proves that AI-assisted development isn’t just for demos—it can produce production-grade, consumer-scale apps in weeks, not months, reshaping how we think about software delivery timelines.