In development
Tarn for Android
- Requires
- Android 9 or later
- Shell
- Native Shell 0.5.0, Android views
- Engine
- System WebView
- Checked on
- Phone and 10-inch tablet emulators, Android 16
- Install
- None yet; debug APK
The start page on an Android phone. 
The same menu as on iPhone. 
Settings with Strict as the default Shield level. 
Spaces live in profiles; a profile keeps its own cookies. 
Links to other apps ask first.
How does the private space work on Android?
The system WebView has no in-memory store, so the private space cannot keep data off disk. It runs in its own process with its own WebView folder inside the app's encrypted storage, deleted when the space closes and, after a crash or force-stop, at the next app start. Its screen is left out of Recents screenshots and its text fields opt out of keyboard learning.
The tab grid on a 10-inch tablet.
What works on Android today?
The checks ran on the Android 16 phone and tablet emulators with WebView 157, against a local test server.
- Tabs, spaces and profiles, each profile with its own WebView data
- A private space in a separate process, its folder deleted when it closes and swept at the next launch
- Shield: Standard, Strict and Lockdown, local addresses blocked from public pages, HTTPS-only upgrades
- Find in page, zoom, prompts, downloads, and links to other apps that ask first
How is it built?
The same Native Shell app as on iPhone and iPad runs inside a small Android host app. Tarn's own web-view component wraps the system WebView, and every request passes Shield's rules in Rust before WebView loads it. WebView renders in its own isolated process.
Can I build or try it?
Yes, with access to the repository, nsh 0.5.0, the Android SDK and NDK and JDK 17 or later. The script builds a debug APK.
cd mobile && cargo test --locked # shell and UI tests on the host
mobile/android/build.sh # debug APK (ANDROID_HOME, NDK, JDK 17+)Questions
Is Tarn on the Play Store?
No. The Android app has no signed or store build yet; the repository builds a debug APK.
Which Android version does Tarn need?
Android 9 or later.
Which engine does Tarn use on Android?
The system WebView, which Google updates through the Play Store. Tarn ships no Chromium or Gecko of its own on Android.
Does the private space keep data on Android?
Briefly. The system WebView has no in-memory store, so private browsing runs in a separate process with its own folder, deleted when the space closes or at the next start after a crash. Until then it is readable with root access or a forensic image of the unlocked device.
Does it work on tablets?
Yes. It was checked on a 10-inch tablet emulator as well as a phone, in portrait and landscape.
What it does not do yet
- No signed or Play Store build yet, and never run on a physical device: only in the emulator.
- The private space's data is on disk while it is open, and after a crash until the next start; deletion is a file unlink, not a secure erase.
- While the private space is in front, the launcher's live Recents tile shows it; only the stored snapshot is blank.
- Blocking requests to your local network is not yet complete on Android.
- TalkBack has not been run.
Last reviewed
Try Tarn on your Mac
No account to make and nothing sent home. macOS 14 or later; other platforms are in development.