Convert Progressive Web App (PWA) to Android App (APK)
Progressive Web App or PWA is an excellent way enabling your website visitors adding an icon on their mobile device desktop for quick and easy access. In addition to other benefits, PWA offers native app-like experience while still being a website just with manifest like this added. But it's much more difficult to engage user to hit Add to home while visiting your website on regular browser than to ask him/her to install an app from Play Store. Let's look into how to convert PWA to full-blown Android app that can be distributed as APK or via regular app store.
First we need to introduce ourselves to Trusted Web Activity or TWA:
Trusted Web Activity is a new way to open your web-app content such as your Progressive Web App (PWA) from your Android app using a protocol based on Custom Tabs.
So essentially whatever will be presented to user screen is website content which would look exactly the same opened in usual browser. Afterall, most apps need internet connection to work, right?
TWA can be built into APK or prepared as Android App Bundle (AAB) which is required by Play Sore following this guide or by walking this step-by-step post available to web monetization subscribers below.
Make sure NodeJS v.16 in installed in your system. On Ubuntu it goes like this:
# Using Ubuntu curl -fsSL https://deb.nodesource.com/setup_16.x | sudo -E bash - sudo apt-get install nodejs
Node Package Manager is installed using this command:
sudo apt install npm
Make npm user directory based
To avoid permission errors such as:
Error: EACCES: permission denied, access '/usr/local/lib'
npm in user's local directory:
mkdir ~/.npm-global npm config set prefix '~/.npm-global'
Now edit user's shell config file
~/.profile by adding:
And propagate these changes:
In case needed to install up-to-date
npm install -g firstname.lastname@example.org
Bubblewrap will build our PWA / TWA into APK. Install:
npm i -g @bubblewrap/cli
Build your APK: initialize project
Now it's time to build. Have your PWA manifest file URL ready – in my case it is
https://inretio.dev/superpwa-manifest.json – you will be asked for it to initiate the process.
Initialize project providing URL as
bubblewrap init --manifest=https://inretio.dev/superpwa-manifest.json
Script will ask to install JDK 8 and Android SDK to
~/.bubblewrap – make sure to allow it.
Here is how wizard will look like:
bubblewrap init --manifest=https://inretio.dev/superpwa-manifest.json ,-----. ,--. ,--. ,--. | |) /_,--.,--| |-.| |-.| |,---.,--. ,--,--.--.,--,--.,---. | .-. | || | .-. | .-. | | .-. | |.'.| | .--' ,-. | .-. | | '--' ' '' | `-' | `-' | \ --| .'. | | \ '-' | '-' ' `------' `----' `---' `---'`--'`----'--' '--`--' `--`--| |-' `--' Initializing application from Web Manifest: - https://inretio.dev/superpwa-manifest.json WARNING: Trusted Web Activities are currently incompatible with applications targeting children under the age of 13. Check out the Play for Families policies to learn more. https://play.google.com/console/about/families/ Web app details (1/5) The application generated by Bubblewrap will open a Progressive Web App when started from the Android launcher. Please enter the following details about the PWA: - Domain: the domain / origin where the PWA is hosted. Example: example.com - URL path: an URL path relative to the root of the origin, opened when the application is started from the home screen. Examples: - To open https://example.com/: / - To open https://example.com/path-to-pwa/: /path-to-pwa/ ? Domain: inretio.dev ? URL path: / Android app details (2/5) Please, enter details regarding how the Android app will look when installed into a device: - Application name: the name used in most places, including the App information screen and on the Play Store. - Short name: an alternate name for the app, limited to 12 characters, used on a device launch screen. - Application ID: also known as Package Name, this is the unique identifier for the application on an Android device or the Play Store. The name must contain at least two segments, separated by dots, each segment must start with a letter and all characters must be alphanumeric or an underscore (_). - Display mode: how the app will be displayed on the device screen when started. The default mode, used by most apps, is standalone. fullscreen causes the device status bar and navigation bars to be removed and is suitable for games or media players. For more information on the status bars and navigation bar on Android, go to: - https://material.io/design/platform-guidance/android-bars.html. - Status bar color: sets the status bar color used when the application is in foreground. Example: #7CC0FF ? Application name: Inretio Services ? Short name: Inretio ? Application ID: dev.inretio.twa ? Starting version code for the new app version: 1.0.0 ? Display mode: standalone ? Orientation: any ? Status bar color: #2D5016 Launcher icons and splash screen (3/5) The Android app requires an image for the launcher icon. It also displays a splash screen while the web content is loading, to avoid displaying a flash of a blank white page to users. - Splash screen color: sets the background colour used for the splash screen. Example: #7CC0FF - Icon URL: URL to an image that is at least 512x512px. Used to generate the launcher icon for the application and the image for the splash screen. - Maskable Icon URL (Optional): URL to an image that is at least 512x512px to be used when generating maskable icons. Maskable icons should look good when their edges are removed by an icon mask. They will be used to display adaptive launcher icons on the Android home screen. ? Splash screen color: #CAE5C7 ? Icon URL: https://inretio.dev/wp-content/uploads/2021/08/inretio_chip_512x512.png ? Maskable icon URL: https://inretio.dev/wp-content/uploads/2021/08/inretio_chip_512x512.png Optional Features (4/5) - Include app shortcuts: This question is only prompted if a 'shortcuts' section is available on the input Web Manifest. When answered “yes”, Bubblewrap uses the information to generate shortcuts on the Android app. Read more about app shortcuts at https://web.dev/app-shortcuts/. - Monochrome icon URL: URL to an image that is at least 48x48px to be used when generating monochrome icons. Monochrome icons should look good when displayed with a single color, the PWA's theme_color. They will be used for notification icons. ? Monochrome icon URL: https://inretio.dev/wp-content/uploads/2020/04/inretio-chip_48x48.png ? Include support for Play Billing (this relies on alpha dependencies)? No ? Request geolocation permission? No Signing key information (5/5) Please, enter information about the key store containing the keys that will be used to sign the application. If a key store does not exist on the provided path, Bubblewrap will prompt for the creation of a new keystore. - Key store location: The location of the key store in the file system. - Key name: The alias used on the key. Read more about Android signing keys at: https://developer.android.com/studio/publish/app-signing ? Key store location: /home/gytis/inretio_pwa_app/android.keystore ? Key name: android Generating Android Project. >> [████████████████████████████████████████] 100% Signing key creation An existing key store could not be found at "/home/gytis/inretio_pwa_app/android.keystore". ? Do you want to create one now? Yes ? First and Last names (eg: John Doe): Gytis Repecka ? Organizational Unit (eg: Engineering Dept): IT ? Organization (eg: Company Name): Inretio, MB ? Country (2 letter code): LT ? Password for the Key Store: ****** ? Password for the Key: ****** keytool Signing Key created successfully Project generated successfully. Build it by running bubblewrap build
Notice signing key is greated in
android.keystore – this will be important later.
Now build app by running
bubblewrap build – process will look like this:
bubblewrap build ,-----. ,--. ,--. ,--. | |) /_,--.,--| |-.| |-.| |,---.,--. ,--,--.--.,--,--.,---. | .-. | || | .-. | .-. | | .-. | |.'.| | .--' ,-. | .-. | | '--' ' '' | `-' | `-' | \ --| .'. | | \ '-' | '-' ' `------' `----' `---' `---'`--'`----'--' '--`--' `--`--| |-' `--' Please, enter passwords for the keystore /home/gytis/inretio_pwa_app/android.keystore and alias android. ? Password for the Key Store: ****** ? Password for the Key: ****** Building the Android App... - Generated Android APK at ./app-release-signed.apk - Generated Android App Bundle at ./app-release-bundle.aab Failed to run the PWA Quality Criteria checks. Skipping.
To check if APK works, install it onto Android device using adb:
adb devices List of devices attached xxxxxxxxxxxxxxxxxxxx device adb install app-release-signed.apk Success
Now app should be available on the phone. Note: to make sure it does not display browser bar, set up Digital Assets Links.
Publish to Play Store
To publish app on Play Store you will need to setup developer account, pay $25 and submit your
app-release-bundle.aab file via Play Console.
Few words about app signing:
If you opt in to Play App Signing, then the signing key that Bubblewrap generated and used to sign your app becomes the “upload key”. Whether you choose to use the Bubblewrap generated key as your signing or upload key, you should guard and keep the key private. We don't recommend committing it to version control. Instead, limit the number of individuals with access to it.
My name is Gytis Repečka, I am Solution Architect focusing on Data Vault automation. Experienced data professional with over 10 years of experience designing and implementing Data Warehouse solutions based on Teradata, Informatica PowerCenter, Oracle Data Integrator, PostgreSQL, AWS. I enjoy using, promoting and contributing to open source software and love communicating about tech to both advanced and non-tech people. Visit Inretio for consulting services. Mention me @email@example.com on Mastodon.