TWA — Trusted Web Activity (PWA to Play Store)

Code

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<title>TWA — Trusted Web Activity (PWA to Play Store)</title>
<style>
  *,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
  body{
    font-family:system-ui,-apple-system,sans-serif;
    background:#0a0a0f;
    color:#e2e8f0;
    padding:24px;
    line-height:1.6;
  }
  .card{
    background:rgba(255,255,255,0.03);
    border:1px solid rgba(255,255,255,0.08);
    border-radius:12px;
    padding:28px;
    max-width:720px;
    margin:0 auto;
  }
  h1{
    font-size:1.5rem;
    font-weight:700;
    margin-bottom:4px;
    color:#fff;
  }
  .subtitle{
    color:#94a3b8;
    font-size:0.875rem;
    margin-bottom:24px;
  }
  .section-title{
    font-size:0.75rem;
    font-weight:600;
    text-transform:uppercase;
    letter-spacing:0.08em;
    color:#22d3ee;
    margin-bottom:12px;
    margin-top:24px;
  }
  .prereqs{
    list-style:none;
    margin-bottom:16px;
  }
  .prereqs li{
    font-size:0.82rem;
    color:#e2e8f0;
    padding:5px 0;
  }
  .prereqs li::before{
    content:"\25B8 ";
    color:#3b82f6;
    margin-right:6px;
  }
  .cli{
    font-family:'SF Mono',SFMono-Regular,Consolas,'Liberation Mono',Menlo,monospace;
    font-size:0.8rem;
    background:rgba(34,211,238,0.08);
    color:#22d3ee;
    padding:8px 12px;
    border-radius:6px;
    margin-bottom:8px;
    overflow-x:auto;
    white-space:nowrap;
  }
  .cli-label{
    font-size:0.72rem;
    color:#64748b;
    margin-bottom:4px;
    margin-top:10px;
  }
  .tree{
    font-family:'SF Mono',SFMono-Regular,Consolas,'Liberation Mono',Menlo,monospace;
    font-size:0.78rem;
    color:#94a3b8;
    background:rgba(255,255,255,0.02);
    border:1px solid rgba(255,255,255,0.06);
    border-radius:8px;
    padding:14px 18px;
    line-height:1.7;
    margin-bottom:16px;
  }
  .tree .folder{color:#3b82f6}
  .tree .file{color:#e2e8f0}
  .tree .comment{color:#64748b;font-style:italic}
  .flow{
    display:flex;
    align-items:center;
    gap:0;
    flex-wrap:wrap;
    margin-bottom:16px;
    padding:16px;
    background:rgba(255,255,255,0.02);
    border:1px solid rgba(255,255,255,0.06);
    border-radius:8px;
  }
  .flow-step{
    background:rgba(34,211,238,0.08);
    border:1px solid rgba(34,211,238,0.2);
    border-radius:6px;
    padding:8px 12px;
    font-size:0.78rem;
    color:#22d3ee;
    font-weight:500;
    white-space:nowrap;
  }
  .flow-arrow{
    color:#64748b;
    font-size:0.85rem;
    padding:0 6px;
  }
  .code-block{
    font-family:'SF Mono',SFMono-Regular,Consolas,'Liberation Mono',Menlo,monospace;
    font-size:0.73rem;
    color:#94a3b8;
    background:rgba(255,255,255,0.02);
    border:1px solid rgba(255,255,255,0.06);
    border-radius:8px;
    padding:14px 18px;
    line-height:1.65;
    margin-bottom:16px;
    overflow-x:auto;
    white-space:pre;
  }
  .code-block .kw{color:#22d3ee}
  .code-block .str{color:#3b82f6}
  .code-block .comment{color:#64748b;font-style:italic}
  .asset-note{
    font-size:0.8rem;
    color:#94a3b8;
    background:rgba(59,130,246,0.06);
    border-left:3px solid #3b82f6;
    padding:10px 14px;
    border-radius:0 6px 6px 0;
    margin-bottom:16px;
  }
  .asset-note strong{color:#e2e8f0}
  .links{
    display:flex;
    gap:12px;
    flex-wrap:wrap;
    margin-top:20px;
    padding-top:16px;
    border-top:1px solid rgba(255,255,255,0.06);
  }
  .links a{
    font-size:0.78rem;
    color:#3b82f6;
    text-decoration:none;
    padding:4px 10px;
    border:1px solid rgba(59,130,246,0.3);
    border-radius:6px;
    transition:background 0.2s;
  }
  .links a:hover{background:rgba(59,130,246,0.1)}
</style>
</head>
<body>
<div class="card">
  <h1>TWA &mdash; Trusted Web Activity</h1>
  <p class="subtitle">Wrap any PWA as an Android app and publish to Google Play Store. No Java/Kotlin required.</p>

  <div class="section-title">Prerequisites</div>
  <ul class="prereqs">
    <li>PWA with a valid web app manifest</li>
    <li>HTTPS hosting</li>
    <li>Android SDK installed (or let Bubblewrap download it)</li>
  </ul>

  <div class="section-title">Bubblewrap CLI Commands</div>
  <div class="cli-label">Initialize from your PWA manifest:</div>
  <div class="cli">bubblewrap init --manifest=https://your-pwa.com/manifest.webmanifest</div>
  <div class="cli-label">Build the signed APK/AAB:</div>
  <div class="cli">bubblewrap build</div>

  <div class="section-title">Generated Project</div>
  <div class="tree">
    <span class="folder">app/</span><br/>
    &nbsp;&nbsp;<span class="folder">src/main/</span><br/>
    &nbsp;&nbsp;&nbsp;&nbsp;<span class="file">AndroidManifest.xml</span><br/>
    &nbsp;&nbsp;&nbsp;&nbsp;<span class="folder">res/</span><br/>
    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span class="folder">mipmap-*/</span> <span class="comment"># Launcher icons</span><br/>
    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span class="folder">values/</span><span class="file">strings.xml</span><br/>
    <span class="folder">gradle/</span><br/>
    <span class="file">build.gradle</span><br/>
    <span class="file">twa-manifest.json</span> <span class="comment"># Bubblewrap config</span><br/>
  </div>

  <div class="section-title">Setup Flow</div>
  <div class="flow">
    <span class="flow-step">PWA</span>
    <span class="flow-arrow">&rarr;</span>
    <span class="flow-step">bubblewrap init</span>
    <span class="flow-arrow">&rarr;</span>
    <span class="flow-step">Build APK</span>
    <span class="flow-arrow">&rarr;</span>
    <span class="flow-step">Asset Links</span>
    <span class="flow-arrow">&rarr;</span>
    <span class="flow-step">Play Store</span>
  </div>

  <div class="section-title">Digital Asset Links</div>
  <div class="asset-note">
    <strong>Required:</strong> Place <code>assetlinks.json</code> at <code>/.well-known/assetlinks.json</code> on your domain to prove ownership and hide browser chrome.
  </div>
  <div class="code-block"><span class="comment">// .well-known/assetlinks.json</span>
[{
  <span class="str">"relation"</span>: [<span class="str">"delegate_permission/common.handle_all_urls"</span>],
  <span class="str">"target"</span>: {
    <span class="str">"namespace"</span>: <span class="str">"android_app"</span>,
    <span class="str">"package_name"</span>: <span class="str">"com.your.package"</span>,
    <span class="str">"sha256_cert_fingerprints"</span>: [<span class="str">"AA:BB:CC:..."</span>]
  }
}]</div>

  <div class="links">
    <a href="https://developer.android.com/develop/ui/views/layout/webapps/guide-trusted-web-activities-version2" target="_blank" rel="noopener">TWA Docs</a>
    <a href="https://github.com/GoogleChromeLabs/bubblewrap" target="_blank" rel="noopener">Bubblewrap CLI</a>
    <a href="https://developers.google.com/digital-asset-links" target="_blank" rel="noopener">Digital Asset Links</a>
  </div>
</div>
</body>
</html>

Trusted Web Activities let you publish any PWA to the Google Play Store as a native Android app. No Java, no Kotlin — just your existing web app wrapped in a Chrome Custom Tab without the browser UI.

What is a TWA?

A Trusted Web Activity is an Android activity that launches a full-screen Chrome Custom Tab. When Digital Asset Links verification passes, the browser chrome (address bar, toolbar) is completely hidden, making it look and feel like a native app.

Requirements:

A PWA with a valid web app manifest
HTTPS hosting
Android SDK (for building the APK/AAB)

Setup with Bubblewrap CLI

Bubblewrap (2.9k stars) is Google Chrome Labs’ CLI that generates a complete Android project from your PWA manifest.

1. Install Bubblewrap

npm i -g @bubblewrap/cli

2. Initialize from your PWA manifest

bubblewrap init --manifest=https://your-pwa.com/manifest.webmanifest

This prompts for your signing key, package name, and launcher icon, then generates a full Android project.

3. Build the APK

bubblewrap build

Outputs app-release-signed.apk and app-release-bundle.aab (for Play Store upload).

Generated Project Structure

app/
  src/main/
    AndroidManifest.xml
    res/
      mipmap-*/        # Launcher icons (auto-generated)
      values/
        strings.xml
gradle/
build.gradle
twa-manifest.json      # Bubblewrap config (re-run init to update)

Digital Asset Links

For the browser chrome to disappear, you must prove you own the domain. Place this file at https://your-pwa.com/.well-known/assetlinks.json:

[{
  "relation": ["delegate_permission/common.handle_all_urls"],
  "target": {
    "namespace": "android_app",
    "package_name": "com.your.package",
    "sha256_cert_fingerprints": ["AA:BB:CC:..."]
  }
}]

Get your signing key fingerprint with:

keytool -list -v -keystore your-keystore.jks

The Full Flow

Build your PWA — manifest, service worker, HTTPS
bubblewrap init — generate Android project from manifest
bubblewrap build — produce signed APK/AAB
Deploy assetlinks.json — verify domain ownership
Upload to Play Store — publish the AAB via Google Play Console