Hew Playground on Android

Learn with examples and keep portable copies of your code in the Android beta.

Join the Hew Playground Android beta, follow Google Play’s opt-in steps and install the app. Android is in development; this public pre-release can change as work continues. Keep exported copies of code you want to retain.

This guide follows the current Android app source, which bundles the official Hew 0.9.2 compiler and sandbox engine. Its native screenshots show the learner and document screens captured from a signed 0.6.1 build. The beta installed through Play can be an earlier version; names and available features may vary.

Open an example and run it

Open Library → Examples. Older builds show Examples directly in the toolbar.
Choose Hello World to load it into the editor.
Tap Run and read the Output panel below the code.
Change the string printed by println, then tap Run again.

Native Android Examples picker with Hello World and Fibonacci cards — Choose a bundled example to start from code that matches the app.

You can also type this small program:

fn main() {
    println("Hello from Android!");
}

The editor changes to the selected example or lesson. Keep a local file or export the code before replacing work you want to retain.

Edit and navigate code

Tap the editor to type. It provides line numbers, syntax highlighting, auto-indent and bracket/quote pairing. Settings controls font size, line numbers and analysis preferences. When the local compiler is ready, completion chips, diagnostics, hover information and the Symbols outline help you inspect code. Long-press in the editor for hover information; tap a completion chip to insert it.

Android editor with Library, My Files and Symbols controls and successful actor-program output — The editor and Output panel after running the multiple-actor example.

Drag the divider or use the output-panel control to adjust how much code and output you see. A larger screen gives the adaptive layout more room.

Read output and errors

A successful run prints its standard output in Output. Compile errors, runtime failures and connection errors appear there instead of being treated as successful output. Fix the first relevant diagnostic, then run again. A program that does not print can finish successfully with an empty output panel.

The current Android implementation tries the on-device sandbox when it is ready. If it is unavailable, or the program is rejected only for native-only capabilities, execution can use the remote service and send the source to the server. Genuine compile errors and other local failures stay visible. Android does not currently expose the iOS On device/Remote engine chooser.

On-device supported programs can run offline after the engine is ready. A remote run needs internet and the service’s supported capabilities. If you need to keep code off the network, do not assume pressing Run is local in every situation. Check your installed version and the available engine status before running sensitive source.

Keep local files and export a backup

Choose My Files. It stores working copies inside the app and auto-saves them while you edit. Use New File to create one, tap a file to reopen it, and use its menu to rename or delete it.

Android My Files showing Device Storage, Import, Export current file and saved Hew documents — My Files keeps app-local documents. Import and Export current file use Android storage providers.

Import copies a .hew file from the Android document picker into the app.
Export current file writes the current editor contents as a portable .hew file to the chosen destination.
Export again after later changes to update an external copy. Cancelling the picker does not create an exported backup.

Local documents are kept in app-private storage and are excluded from Android backup/device transfer in the current implementation. Export important code before uninstalling, clearing app data or changing devices. If a storage provider fails, retain the working copy and retry elsewhere.

Tap the Share icon in the top bar to create a hew.run link and open Android’s share chooser. In Settings → Sharing & Links, choose the default share format:

Format	What happens
Auto	Creates an inline link if it fits; otherwise uploads source for a server-backed link.
Always Inline	Keeps compressed source in the URL fragment; reports an error if the program is too large.
Always Server	Uploads source to create a short link; requires a connection.

An inline link still contains the program. Anyone with the link can read it. Remove secrets and private data before sharing. If link creation fails, check the connection or export a .hew file instead. Supported share links can open in the app when Open share links in-app is enabled.

Learn with tutorials and Quick Ref

Choose Library → Tutorials for guided lessons. Read a lesson, then use Try it in the Editor to load its code. Tutorial progress and settings are stored locally.

Native Android Learn Hew list showing lesson progress and Hello World, Variables and Constants, and Functions — The bundled tutorial list keeps progress on the device.

Library → Documentation opens Quick Ref, Docs and Learn. Quick Ref’s syntax cards are bundled and available offline; Try It loads a snippet. Docs and Learn open live website content and require internet.

When you want the ideas behind the syntax, start with the core concepts map. Use the language reference and standard-library guide when you need exact rules or API details. These website pages track the current Hew release and can be newer than the compiler bundled with your installed beta.

Android Quick Ref showing an actor syntax card and Try It button beside Docs and Learn tabs — Quick Ref works offline. Docs and Learn use the live website.

Troubleshoot a beta session

Run is unavailable or fails offline: wait for the local engine to start; reconnect if the run needs the remote service.
Language-service banner: read its loading/error status. Missing diagnostics are not a successful compile result.
Syntax differs from a website example: start from a bundled example or update the app; the installed beta and website compiler may differ.
No printed output: expand Output and check errors, then try Hello World to distinguish a quiet program from a failed run.
Sharing or importing fails: keep the current code, check the connection or provider, and retry. Use an exported file when a link is unsuitable.

Continue with the iPhone/iPad guide or mobile guide overview. Both guides are also in the printable manual.