Packaging and publishing applications for Android

Introduction

This tutorial will guide you in packaging an application for Android and publishing it in one of KDE's F-Droid repositories.

We assume that there is already a working blueprint for the application you want to package and publish. If not then read the tutorial on building applications for Android.

We use Kongress as example.

Packaging the application

In the first step we configure the CI/CD pipeline of Kongress in KDE's GitLab, so that it creates APKs. We do this by adding the template /gitlab-templates/craft-android-qt6-apks.yml to the .gitlab-ci.yml file of Kongress:

include:
  - project: sysadmin/ci-utilities
    file:
      [...]
      - /gitlab-templates/craft-android-qt6-apks.yml

This template adds four jobs to CI/CD pipeline of Kongress:

• craft_android_qt66_arm32, craft_android_qt66_arm64, and craft_android_qt66_x86_64 which build APKs for three different processor architectures, and
• fdroid_apks_qt66 which we will look at a bit later.

When we now run a CI/CD pipeline for Kongress then, after successful completion, the three craft_android_* jobs will have created APKs which we can download by browsing the job artifacts. You'll find the APKs in the folder kde-ci-packages/.

By default, the APKs are not signed. If you want to install such an APKs on your device then you have to sign it as described in the previous tutorial.

Signing the APKs

Now we configure our CI/CD system, so that it signs the APKs created by the CI/CD pipeline. The CI/CD system signs APKs on project branches which are cleared for APK signing. We want to sign the APKs created for the 24.02 release branch. Project branches are cleared for APK signing by adding them to the project settings of the apksigner in the ci-utilities repository. To clear the 24.02 release branch of Kongress for APK signing we add the following to apksigner-projects.yaml:

utilities/kongress:
  applicationid: org.kde.kongress
  branches:
    release/24.02:

See the documentation of the apksigner's project settings for details.

When we now run a CI/CD pipeline for Kongress on the release/24.02 branch then the three craft_android_* jobs will create signed APKs which you can install on your device without having to sign them yourself.

Publishing the application on F-Droid

Now that we have signed APKs created for the latest release branch of Kongress we want to publish them in our F-Droid repository to make it easier to install and update Kongress. But before we do this we download the APK, install it on our device and perform a more or less thorough test to ensure that the APK works.

After we have verified that the APK works we configure the CI/CD system to publish the APKs created for the 24.02 release branch of Kongress in our Android Release Builds F-Droid repository. For this we add the following to the project settings of the fdroidpublisher:

utilities/kongress:
  applicationid: org.kde.kongress
  branches:
    master:
    release/24.02:
      repository: stable-releases

These settings tell the CI/CD system that the APKs built on the master branch shall be published in the default repository (which is the nightly builds repository) and that the APKs built on the release/24.02 branch shall be published in the release builds repository.

See the documentation of the fdroidpublisher's project settings for details.

Summary

In this tutorial we have learned how to configure KDE's CI/CD system to package an application for Android and how to publish it in one of KDE's F-Droid repositories so that our users can easily install it.