nOS4 is a recreation of iOS 4, running in the browser.

Why

Software used to have weight. Buttons felt like you actually press on them. Switches looked like you could flick them. A list sat on linen, a note sat on legal paper, and a reflection under the dock told you where the glass was. Every pixel was doing a job.

That craft is worth preserving, and the best way to understand something is to rebuild it. So that's how nos4 born.

What's inside

Twenty-three apps — Safari, Mail, Messages, Phone, Maps, iPod, Photos, Camera, Notes, Weather, Stocks, Clock, Calculator, Compass, Voice Memos, Contacts, Settings, App Store, iTunes, Game Center and two games.

Underneath sit sixteen frameworks:

Nothing imports upward. Foundation → CoreGraphics → UIKit → SpringBoard → apps.

The apps

2010s Rich

Build

You need Node 22.6+ and pnpm 10+.

git clone https://github.com/1etu/nos4.git
cd nos4
pnpm install

Then run the phone:

pnpm -C apps/Phone dev

Game Center is the one part that needs a server. It is optional and everything else do work without it. To run it, put a Postgres connection string in a root .env:

DATABASE_URL=postgresql://…

Apply services/GameCenterService/schema/*.sql in order, then pnpm service.

Credits

The OldOS Project by Zane (@zzanehip) — Its asset catalogue is where nOS4's artwork comes from, nOS4 shares no code with it and every screen here was rewritten from scratch. Without it there would be nothing to measure.

Maps are drawn with OpenStreetMap tiles, geocoded by Nominatim and routed by OSRM. Weather comes from Open-Meteo. The App Store and iTunes read Apple's public iTunes Search and RSS feeds. Type is set in Inter and Helvetica Neue.

iPhone, iOS and the app designs recreated here are trademarks of Apple Inc. This is an independent tribute, not affiliated with or endorsed by Apple.