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@iSoron @Broxzier @Gelma

Build the project

This pages describes how to download and build the app from the source code. If you are having trouble building the project, please do not hesitate to open a new issue.


Build using Android Studio

Step 1: Install git

The package git is required for downloading the source code of the app and submitting changes GitHub. Please see the git book for further instructions. If you are planning to submit pull requests in the future, it is recommended to generate and configure your SSH keys.

Step 2: Download and install Android Studio

Although Android Studio can be downloaded from their official website, a much better option is to install it through JetBrains Toolbox. This tool, developed by the same developers of Android Studio, allows you to easily upgrade and downgrade the IDE, or switch between stable, beta and canary versions. After downloading and installing JetBrains Toolbox, simply click the install button near Android Studio to install the newest stable version of IDE. Beta and canary versions have not been tested and may not work correctly.

After installation, launch Android Studio. If this is the first time you launch it, you will need to go through a wizard to setup the IDE. The default options should work fine. The wizard will download all additional components necessary for development, including the emulator, so it may take a while.

Step 3: Download the source code

To create a complete copy of the source code repository, open the terminal (Linux/macOS) or Git Bash (Windows), navigate to the desired folder, then run:

git clone

The repository will be downloaded to the directory uhabits.

Step 4: Open and run the project on Android Studio

  1. Launch Android Studio and select "Open an existing Android Studio project".
  2. When the IDE asks you for the project location, select uhabits and click "Ok".
  3. Android Studio will spend some time indexing the project. When this is complete, click the toolbar icon "Sync Project with Gradle File", located near the right corner of the top toolbar.
  4. The operation will likely fail several times due to missing Android SDK components. Each time it fails, click the link "Install missing platforms", "Install build tools", etc, and try again.
  5. To test the application, create a virtual Android device using the menu "Tools" and "AVD Manager". The default options should work fine, but feel free to customize the device.
  6. Click the menu "Run" and "uhabits-android". The application should launch.

Build from the command line

The following instructions were tested on Ubuntu Linux 18.04 LTS and may need to be modified for other operating systems.

Step 1: Install basic packages

To build the application, some basic packages are required. The package git is required to download the source code, while openjdk-8-jdk-headless is required for compiling Java and Kotlin files.

sudo apt-get update
sudo apt-get install -y git openjdk-8-jdk-headless

IMPORTANT: Newer JDK versions have not been tested and may not work correctly.

Step 2: Install Android SDK tools

The Android SDK tools contains many necessary tools for developing and debugging Android applications. It can be obtained as part of Android Studio, but, for simple command line usage, it can also be downloaded individually.

  1. Download the file (or a newer version) from, and extract it somewhere. In this guide, we assume that it was extracted to /opt/android-sdk/tools; that is, the script /opt/android-sdk/tools/bin/sdkmanager should exist.

  2. Append the following lines to ~/.profile, so that other tools can locate your Android SDK installation. It is necessary to restart your terminal for these changes to take effect.

export PATH="$PATH:/opt/android-sdk/tools/bin"
export PATH="$PATH:/opt/android-sdk/platform-tools"
export ANDROID_HOME="/opt/android-sdk"
  1. Accept all Android SDK licenses, by running
yes | sdkmanager --licenses

Step 3: Download the source code

To create a complete copy of the source code repository, navigate to your home directory and run:

git clone

The repository will be downloaded to the directory uhabits.

Step 4: Compile the source code

  1. Navigate to the directory uhabits
  2. Run ./gradlew assembleDebug --stacktrace

If the compilation is successful, a debug APK will be generated somewhere inside the folder uhabits-android/build/. Currently, the full path is the following, but it may change in the future:


The APK can be installed using the tool adb, which should have been automatically installed at /opt/android-sdk/platform-tools/adb during compilation of the project.