I built an Android OS in the browser

In plain words

I built an Android OS in the browser is a web-based recreation of Android OS that runs entirely in a browser window. Launched in May 2026, it appeals to developers, tech enthusiasts, and anyone curious about operating system design. The project stands out by bringing a full mobile operating system environment to desktop browsers, eliminating the need for emulators or virtual machines while maintaining authentic Android functionality and interface elements.

written from the facts on this page · September 2026

From the sources

After burning through tens of billions of tokens, I built an Android-like OS that runs entirely in the browser. Over the past few months, we built MobileGym: a fully browser-based, Android-like simulation environment implemented in TypeScript + React. It currently includes 28 simulated apps, including WeChat, Alipay, Xiaohongshu/RED, bilibili, X, Reddit, WeChat Read, China Railway 12306, Tencent Meeting, Spotify, and eBay, and others

Snapshot · time-travel · inject cross-app data while the simulator keeps running. Use the built-in demo model, or connect your own OpenAI-compatible vision endpoint. MobileGym is a verifiable and highly parallel simulation platform for mobile GUI agent research — the first to make online RL training and deterministic evaluation feasible on real-world daily apps , long a structural blind spot of real-device pipelines. It covers 28 mobile apps (12 daily + 16 system) in the browser. Across the released validation suite, programmatic state judges show no false accept/reject cases over 416 parameterized task templates (vs. 10.2% misjudgment when the same real-device trajectories are scored by a…from mobilegym.dev

• 
  Apache Weex2017 · incubator.apache.org · ▲127

  A framework for building mobile cross-platform UIs

• 
  I wrote the book Building Mobile Apps at Scale2021 · mobileatscale.com · ▲357

  The guide for building large, iOS, and Android native apps - with the challenges and common solutions across the industry.

• 
  Jolla (Sailfish OS)2013 · jolla.com · ▲73

  An alternative android OS

• 
  Muscle-Mem, a behavior cache for AI agents2025 · github.com · ▲226

  Hi HN! Erik here from Pig.dev, and today I'd like to share a new project we've just open sourced: Muscle Mem is an SDK that records your agent's tool-calling patterns as it solves tasks, and will deterministically replay those learned trajectories whenever the task is encountered again, falling back to agent mode if edge cases are detected. Like a JIT compiler, for behaviors. At Pig, we built computer-use agents for automating legacy Windows applications (healthcare, lending, manufacturing, etc). A recurring theme we ran into was that businesses already had RPA (pure-software scripts), and…

• 
  Supersonic2014 · appgyver.com · ▲89

  UI framework for building awesome hybrid mobile apps

• WE
  WebGPU enables local LLM in the browser – demo site with AI chat2025 · andreinwald.github.io · ▲145

  Browser LLM demo working on JavaScript and WebGPU. WebGPU is already supported in Chrome, Safari, Firefox, iOS (v26) and Android. Demo, similar to ChatGPT https://andreinwald.github.io/browser-llm/ Code https://github.com/andreinwald/browser-llm - No need to use your OPENAI_API_KEY - its local model that runs on your device - No network requests to any API - No need to install any program - No need to download files on your device (model is cached in browser) - Site will ask before downloading large files (llm model) to browser cache - Hosted on Github…

• 
  Spira Maxima▲578

  Video model that turns script into viral social media videos

  AI · 17d ago · spira.ai

• 
  Rill Browser▲540

  The browser where Claude Code and Codex work beside you

  AI · 17d ago · rill.love

• 
  Germany's new sovereign AI model Kolibri▲424

  Kolibri is Aleph Alpha

  AI · 19d ago · tej.as

• 
  Giving Opus 5.5 a simulated paint canvas▲392

  Paintings by AI models: programs run through a simulation of oil paint.

  AI · 20d ago · stillwet.art

• 
  PixVerse R2▲381

  A real-time world model you can explore and change

  AI · 29d ago · world.pixverse.video

• 
  Hemory▲381

  Keep listening. Searchable memory for your AI agents.

  AI · 30d ago · hemory.com

• 
  Brew ▲900

  Like Claude design for email marketing

  AI · May 2026 · brew.new

• 
  Kilo Code for VS Code▲896

  Parallel agents, diff reviewer, and multi-model comparisons

  Dev tools · May 2026 · kilo.ai

• 
  StoreClaw▲806

  Grow your store profits with agents that know how to sell

  AI · May 2026 · storeclaw.ai

• 
  PollyReach▲795

  Give your agent a real number and voice to make calls.

  AI · May 2026 · pollyreach.ai

• 
  Needle: We Distilled Gemini Tool Calling into a 26M Model▲776

  Hey HN, Henry here from Cactus. We open-sourced Needle, a 26M parameter function-calling (tool use) model. It runs at 6000 tok/s prefill and 1200 tok/s decode on consumer devices. We were always frustrated by the little effort made towards building agentic models that run on budget phones, so we conducted investigations that led to an observation: agentic experiences are built upon tool calling, and massive models are overkill for it. Tool calling is fundamentally retrieval-and-assembly (match query to tool name, extract argument values, emit JSON), not reasoning. Cross-attention…

  Life & fun · May 2026 · github.com

• 
  Files.md – Open-source alternative to Obsidian▲730

  🌱 Private, quiet space for thinking. Simple app for .md files. - zakirullin/files.md

  Dev tools · May 2026 · github.com