How to create a Python application for Android from scratch: a complete guide

Many developers start their journey with the language Python, appreciating it for its readability and powerful libraries. However, when moving to mobile development, a logical question arises: is it possible to use this knowledge to create native applications on Android? The answer is yes, although the process is different from standard web development or server-side scripting. Creating a APKfile from Python code requires an understanding of how compilers work and the specifics of mobile platforms.

Unlike Java or Kotlin, which are native to the Google ecosystem, Python requires the use of special wrapper frameworks. These tools translate your code into a format that the Android virtual machine can understand, or package an interpreter with the application. You have to choose between several popular solutions, each of which has its advantages and disadvantages. The most common way is to use the library Kivy in conjunction with the utility Buildozer.

The process of setting up an environment can seem complicated to a beginner, especially if you have never worked with the Linux command line. However, following clear instructions, you can deploy a working tool in one evening. It is important to understand that the result will be cross-platform: having written the code once, you can run it not only on your phone, but also on a tablet or even a desktop system. This makes the approach extremely effective for prototyping and creating utilities.

Selecting tools and frameworks

The first step is to define a technology stack. Not all libraries are equally suitable for mobile development. For a long time, Kivyremains the market leader in solutions for Python on mobile devices. This is an open source library that allows you to create multi-touch applications with your own graphical interface. It does not use native Android widgets, but draws the interface independently, which guarantees the same look on all devices.

An alternative is the project BeeWare and its set of tools Toga. Unlike Kivy, this framework strives to use native operating system controls. This means that your app will look like a stock Android app rather than a custom interface. However, BeeWare support is still under active development, and some complex functions may be unstable.

For serious projects that require high performance, sometimes they use a combination of Python with C++ via PyQt or PySide, although their integration with mobile assemblies is much more complicated. The choice depends on your goals: if you need a quick prototype or a game with a unique design, choose Kivy. If compliance with Material Design guidelines is important, take a closer look at BeeWare.

• 🐍 Kivy —the most mature ecosystem with a huge number of examples and ready-made widgets.
• 🤖 BeeWare —a promising project for creating native appearance for applications.
• ⚡ PyQt —a powerful tool for complex interfaces, but with a high entry threshold for mobile phones.

⚠️ Attention: The Kivy framework uses its own KV markup language to describe interfaces. Do not try to write the entire UI only in Python - this will make the code cumbersome and difficult to maintain.

Setting up the development environment

Development for Android in Python is almost impossible directly in the Windows or macOS environment without the use of virtual machines or containers. The build tool, which is the de facto standard for Kivy, requires an operating system. This is due to dependencies on specific compilation libraries for the ARM architecture. Buildozer, which is the de facto standard for Kivy, requires an operating system Linux. This is due to dependencies on specific compilation libraries for the ARM architecture.

The easiest way to get the necessary environment is to use a virtual machine with Ubuntu or the WSL2 subsystem (Windows Subsystem for Linux) in Windows 10/11. After installing Linux, you will need to update the repositories and install the base packages for compilation. This is usually done through the terminal with the command sudo apt-get update, followed by installing packages like git, python3, python3-pip and openjdk-11-jdk.

Next you need to install Buildozer itself and its dependencies. The process is automated, but requires a stable Internet connection, as the Android SDK and NDK will be downloaded. These components take up several gigabytes of disk space. Make sure that your virtual disk has at least 10-15 GB of free space allocated, otherwise the build will abort halfway with an out of space error.

pip3 install buildozer
sudo apt install -y build-essential git python3 python3-pip autoconf libtool pkg-config zlib1g-dev libncurses5-dev libncursesw5-dev libtinfo5 cmake libffi-dev libssl-dev

ℹ️ Requirements for tools and SDK versions may change by framework developers. Always check the list of required packages in the official documentation Buildozer or Kivy before starting installation to avoid version conflicts.

Creating the first project and file structure

After setting up the environment, we move on to creating the application itself. The project is initialized with a simple command buildozer init in an empty folder. This command will create a configuration file buildozer.specwhich is the heart of your project. This is where the application name, package name, version, required permissions and list of used libraries are set.

In this file, it is critical to correctly specify package.name and package.domain. The domain usually looks like the return URL of your site or just org.kivy for tests, and the package name must be unique. An error in these fields will result in the application not being installed on the device or will conflict with other apps. The path to the main file is also indicated here source.main, usually this main.py.

The project folder structure should be clean. The main script main.py contains the operating logic, and the file myapp.kv (the name must match the application class in lowercase) is responsible for the appearance. The separation of logic and interface is a key principle of the Kivy architecture. If you break this rule and try to describe the buttons directly in Python code, you will lose the flexibility to change the design later.

Parameter in spec	Description	Example value
title	Name visible to the user	My Calculator
package.name	Package name without domain	mycalculator
orientation	Screen orientation	portrait
requirements	List of libraries	python3,kivy

Writing code and creating an interface

Writing code begins with import necessary modules from the library kivy.app i kivy.uix. You need to create a class that inherits from App, which will be the entry point to the app. The build method in this class should return the root widget of your interface. It can be a simple button, layout or a complex screen with navigation.

Language is used to create interfaces KV. It is declarative and reminiscent of CSS in web development. You describe the hierarchy of widgets, their properties, and event bindings. For example, to change the background color of a button when clicked, you don't write a complex function, but specify the behavior directly in the style rules. This speeds up development significantly.

If your application needs access to phone functions such as camera, vibration or geolocation, standard Python is not enough. This is where the library python-for-android and module plyercome to the rescue. Plyer provides a single API to access hardware capabilities across platforms. You simply import the desired module, for example from plyer import flashlight, and call the method for turning on the flashlight.

⚠️ Attention: Access to sensitive data (camera, microphone, contacts) requires explicit permissions in the file buildozer.spec in the android.permissionssection. Without this, the application will crash when trying to access.

How does hot reload work?

When developing, you can use the Kivy Remote tool. You launch the server on your PC, scan the QR code with the application on your phone, and any changes in the code are instantly displayed on the device without rebuilding the APK.

Building the APK and debugging on the device

When the code is written and tested, the compilation stage begins. The command buildozer -v android debug starts a lengthy build process. The script will download the necessary dependencies, compile the Python code into bytecode, package the resources and create a signed debug key. The first launch can take from 20 minutes to an hour depending on the Internet speed and processor power.

During the build process, you may encounter C library compilation errors. This is often due to mismatched tool versions or the absence of any system packages in the Linux environment. Read the output log carefully: the last lines usually contain an indication of the cause of the failure. Searching for the text of the error in the documentation python-for-android often leads to a ready-made solution.

After successful completion, a file with the extension bin . To install on a smartphone, you need to enable the “For Developers” mode on it and activate “USB Debugging”. By connecting your phone to the computer, you can install the application with the command .apkwill appear in the folder adb install bin/myapp-0.1-debug.apk or simply copy the file to the device and install it manually through the file manager.

# Command to clear previous builds before new compilation
buildozer android clean
Command to build the release version (requires keystore)
buildozer android release

Publishing and optimizing the application

Preparing an application for publication on the Google Play Store requires creating a release signature key. This is done using the utility keytoolincluded in the JDK. You generate a file .keystorethat needs to be stored in a safe place: losing the key means you won't be able to update the application in the future. The file buildozer.spec indicates the path to this key and passwords.

Optimizing the APK size is an important task, since a bare-bones Kivy application with a built-in Python interpreter can weigh 20-30 MB. To reduce the size, you can use the resource compression argument --add-asset or disable unused modules in the build settings. It is also worth testing the application on devices with different screen resolutions to ensure that the adaptive interface works correctly.

The final step is to create a Google Play developer account and upload art, screenshots and descriptions. Remember that the store's policy has become stricter: new accounts must now be tested with 20 users within 14 days before publishing. This is done to combat spam, so plan to launch in advance.

• 🔐 Keystore — a digital key file, without which it is impossible to update the application.
• 📉 Optimization — removal of unused libraries to reduce the weight of the installer.
• 🚀 Release — final assembly optimized for speed, not debugging.

Is it possible to create a game in Python for Android?

Yes, it is possible. The Kivy library was originally created with a focus on multi-touch and gaming. However, for complex 3D graphics, Python may be inferior in performance to engines like Unity or Unreal Engine. For 2D games, puzzles and turn-based strategy games, the performance is quite sufficient.

Why does the application weigh so much?

The APK file packages not only your code, but also the entire Python interpreter, as well as the necessary libraries and dependencies. This ensures that the application will work on any device without first installing Python, but increases the final file size.

Does Internet access work by default?

Yes, basic network access is usually allowed. However, working with specific APIs or background services may require additional permissions in the manifest, which are configured through the file. buildozer.spec.

Can you use ready-made Python libraries?

Most pure Python libraries (without C extensions) work without problems. Libraries that require compilation (for example, numpy, pandas) must be explicitly specified in the requirements section of the specification file so that the build system downloads the correct version for ARM.