How to automatically sign your Android apk using Ionic framework and Crosswalk

Wed 20 May 2015

I discovered a simple trick that can be a great time saver when you are building your app using Ionic Framework and the Crosswalk web view.

In few steps you’ll be able to automate the production of release signed apks of your app, ready to be published on the Google Play Store.

If you are developing an hybrid mobile app using the awesome Ionic Framework and you are targeting the Android platform, I strongly suggest you to use the Crosswalk web view for your app.

The most important advantage using Crosswalk is a consistent platform to deal with, if you don’t like to fix bugs arising from the fragmentation of Android webviews.

Using Crosswalk in your Ionic project is as easy as typing this command:

$ ionic browser add crosswalk

Ionic will take care of setting the building environment for you.

When you want to publish your app on the Google Play Store you have to build the apk in release mode, sign it with a key of your keystore and zipalign the package to optimize it.

Creating the keystore is out of scope of this howto, you can find all the details in the Ionic Documentation.

All of these steps can be automated by creating a file named with your favorite text editor (vi in my case) in your platforms/android/ directory.

cd platforms/android/<br /> vi

In that file you can put only two lines:

storeFile=/path/to/keystore/yourname.keystore<br /> keyAlias=youralias

Of course you have to modify the path to your keystore file and the alias of your key.

Then you can build your release apk with the command:

$ ionic build --release android

A little window will appear asking for the keystore password and the key password. If you don’t want to type the two passwords all times you can write them in the files, adding two lines similar to the following:

storePassword=your_keystore_password<br /> keyPassword=your_key_password

But I suggest to keep your password secret and avoid writing them in a clear text file.

At the end of the build you’ll find your apks in the platforms/android/build/outputs/apk/ directory. With this setup you should find two apks named android-x86-release.apk and android-armv7-release.apk there.

Remember that you have to upload both x86 and armv7 apks to the Play Store, because using Crosswalk your app contains native code which is architecture specific.

Remember to activate the “Advanced mode” in your Developer Console (if you are in “Simple mode” only one apk at a time can be activated) and upload one apk after the other. Google will be clever enough seeing that the apks target two different platforms. For more details on the topic see the Android documentation.

Thanks to baleboy who pointed out in the comments the need to upload both apks to the store.