Developing Android applications in Python from scratch: a complete guide for beginners

Creating mobile applications for Android traditionally associated with Java or Kotlinbut what if you want to use Python a language known for its simplicity and readability? It turns out that this is quite real! Thanks to specialized frameworks like Kivy, BeeWare or Chaquopy, Python can become a full-fledged alternative for developing cross-platform mobile applications, including those that run on Android.

In this guide, we will walk through the entire process - from installing the necessary tools to publishing the finished application in Google Play. You will learn which frameworks are best for beginners, how to set up the development environment, what pitfalls lie along the way and how to get around them. We will pay special attention to integration of Python code with native Android componentswhich often becomes a key problem for beginners.

Important: Python apps for Android do not always show the same performance as native Kotlin applications, but for most tasks (for example, educational projects, prototypes, or applications with moderate load) this is more than enough. If your goal is to create a simple messenger, a tic-tac-toe game, or a utility for working with APIs, Python will do just as well!

Why Python for Android: pros and cons

Before diving into the technical details, let's take a look at whether it's even worth choosing Python for development under Android. This approach has both undeniable advantages and limitations, which are best known in advance.

Pros:

• 🐍 Simplicity of code: Python requires fewer lines of code compared to Java/Kotlin, which speeds up development and reduces the likelihood of errors.
• 🔄 Cross-platform: The same application can be assemble for Android, iOS, Windows or Linux with minimal changes.
• 📚 Rich ecosystem: Access to thousands of libraries (for example, requests for working with APIs or pandas for data analysis).
• 👨‍💻 Low entry threshold: Ideal for beginners who want to quickly see the result without a deep dive into the Android SDK.

Cons:

• ⚡ Performance: Python code runs slower than native code, which is critical for resource-intensive tasks (for example, 3D games or processing video).
• 📱 Limited API access: Not all functions of the Android SDK are available out of the box - sometimes you have to write wrappers in Java.
• 📦 APK size: The finished application may weigh more due to the included Python interpreter.
• 🔧 Difficulties with debugging: Tools like Android Studio do not always work correctly with Python code.

If your application does not require maximum performance (for example, To-Do list, weather application or simple chat bot), Python is a great choice. For games with physics or graphics-intensive applications, it is better to consider Unity (C#) or native development on Kotlin.

Framework choice: Kivy, BeeWare or Chaquopy?

There are several popular tools for creating Android applications in Python. Each of them has its own characteristics, and the choice depends on your tasks. Let's compare the three most common options:

For beginners, we recommend starting with Kivy —it is easier to learn and allows you to quickly get a working application. If native integration is important to you (for example, to work with a camera or GPS), pay attention to Chaquopy, but be prepared for more complex setup.

⚠️ Attention: Chaquopy requires a license for commercial use. Before starting development, check the current conditions on official website.

Installing and configuring the development environment

Before writing code, you need to prepare a working environment. We will use Kivy as the most universal option for beginners. Here's what you'll need:

• 🖥️ A computer with Windows, macOS or Linux.
• 🐍 Installed Python version 3.7 or higher (3.9+ recommended).
• 📱 Android SDK and Java JDK (for building APK).
• 🛠️ Code editor (VS Code, PyCharm or even Notepad++).
• 📱 Device with Android for testing (or emulator).

Step 1. Installing Python and Kivy

Download and install Python from official websiteWhen installing, be sure to check the box Add Python to PATH.

Then install Kivy and additional dependencies via pip:

pip install kivy kivy[base] buildozer

Step 2. Installation Buildozer

Buildozer is a tool for building Python applications in APK. Install it and the necessary dependencies:

pip install buildozer
buildozer init

This command will create a file buildozer.specwhere you specify the build parameters.

Step 3. Setting up Android SDK

Download and install Android Studio from official website. During installation, select components Android SDK and Android NDK. After installation, add the paths to the SDK in. environment variables:

• ANDROID_HOME — path to the folder with the SDK (for example, C:\Users\Username\AppData\Local\Android\Sdk).
• PATH — add %ANDROID_HOME%\tools and %ANDROID_HOME%\platform-tools.

Install Python 3.9+

Install Kivy and Buildozer

Download and configure Android SDK

Add SDK paths to environment variables

Connect Android device in debug mode (or set up an emulator)-->

Creating the first application: "Hello, Android!"

Now that the environment is ready, let's write a simple application that displays the text "Hello, Android!" on the screen. We will use Kivy for the interface and Buildozer for assembly.

Step 1. Create a file main.py

This file will contain the main application code. Open the code editor and enter the following code:

from kivy.app import App
from kivy.uix.label import Label

class HelloApp(App):
def build(self):
return Label(text="Hello, Android!", font_size=50)

if __name__ == "__main__":
HelloApp().run()

Step 2. Configure buildozer.spec

Open the file buildozer.spec and find the following lines (uncomment and edit them):

[app]
title = Hello Android
package.name = helloandroid
package.domain = org.test
source.dir = .
source.include_exts = py,png,jpg,kv,atlas
version = 0.1
requirements = python3,kivy
orientation = portrait
fullscreen = 0

Step 3. Build the APK

Start the build with the command:

buildozer -v android debug

The process may take several minutes. Upon completion, a file will appear in the folder bin Step 4. Install the application on the device helloandroid-0.1-debug.apk.

Step 4. Install the application on your device

Connect your smartphone via USB, turn on Developer mode and USB debugging in the Android settings. Then install the APK with the command:

adb install bin/helloandroid-0.1-debug.apk

Working with the interface: widgets and events

A simple application with one label is good, but let's do something more interactive. Kivy has many widgets to create an interface: buttons, input fields, lists, etc. Let's look at an example of an application with a button that changes text when pressed.

Example: application with a button

Create a file main.py with the following code:

from kivy.app import App
from kivy.uix.boxlayout import BoxLayout
from kivy.uix.button import Button
from kivy.uix.label import Label

class MyApp(App):
def build(self):
layout = BoxLayout(orientation="vertical")
self.label = Label(text="Press the button!", font_size=30)
button = Button(text="Click!", size_hint=(1, 0.2))

button.bind(on_press=self.on_button_press)
layout.add_widget(self.label)
layout.add_widget(button)
return layout

def on_button_press(self, instance):
self.label.text = "The button is pressed! Hurray!"

if __name__ == "__main__":
MyApp().run()

Explanation of the code:

• BoxLayout —a container that arranges widgets vertically or horizontally.
• Button —a button to which an event is attached. on_press.
• bind() —a method for binding an event to a handler function.
• size_hint —a parameter that determines the size of the widget relative to the parent container.

After assembling this code, you will get an application with a button that changes the label text when clicked. This is the basis for creating more complex interfaces.

button = Button(text="Click!", background_color=(0.2, 0.6, 0.8, 1))

Integration with native Android functions

One of the main problems when developing in Python is limited access to native Android API (camera, GPS, sensors, etc.). There are two ways to solve this problem:

1. Use Plyer a library that provides unified access to platform functions.
2. Write a wrapper for Java and connect it via Chaquopy or PyJNIus.

Example: accessing the camera using Plyer

Install Plyer:

pip install plyer

Add to buildozer.spec line requirements = python3,kivy,plyerthen use the following code:

from kivy.app import App
from kivy.uix.boxlayout import BoxLayout
from kivy.uix.button import Button
from kivy.uix.image import Image
from plyer import camera

class CameraApp(App):
def build(self):
layout = BoxLayout(orientation="vertical")
self.image = Image()
button = Button(text="Take photo", size_hint=(1, 0.2))
button.bind(on_press=self.take_picture)
layout.add_widget(self.image)
layout.add_widget(button)
return layout

def take_picture(self, instance):
try:
camera.take_picture(filename="photo.jpg", on_complete=self.display_image)
except NotImplementedError:
self.image.source = "no_camera.png" # Stub if the camera is not available

def display_image(self, filename):
self.image.source = filename
self.image.reload()

if __name__ == "__main__":
CameraApp().run()

Plyer limitations:

• Not all Android features are supported (for example, working with BLE or NFC).
• Some devices may require additional permissions in AndroidManifest.xml.

⚠️ Attention: To work with the camera or geolocation, you must add the appropriate permissions in file buildozer.spec:

android.permissions = CAMERA, ACCESS_FINE_LOCATION

Without this, the application will not be able to access hardware functions.

Building, testing and publishing on Google Play

When the application is ready, it needs to be assembled into the final APK, tested and, if desired, publish to Google Play. Let's look at this process step by step.

1. Final APK assembly

To release, use the command:

buildozer android release

This will create a signed APK in the folder bin. key (if it does not exist, Buildozer will offer to create a new one).

2. Testing on the device

Before publishing, be sure to test the application on several devices with different versions of Android. Pay attention to:

• 🔄 Correct operation of the interface at different resolutions. screen.
• ⚡ Stability (are there any sudden closings or freezes).
• 📶 Working with the network (if the application uses the Internet).
• 🔒 Permission requests (for example, access to the camera or storage).

3. Preparation for publication on Google Play

For publication you will need:

• 💰 Developer account in Google Play Console (one-time payment $25).
• 📝 Description of the application, screenshots, icon (512x512 pixels in size).
• 🎯 AAB-file (Android App Bundle) instead of APK (collected by the team buildozer android aab).
• 📋 Privacy Policy (required if the application collects user data).

4. Uploading to Google Play Console

The publishing process includes the following stages:

1. Creating a new application in Google Play Console.
2. Filling out information about the application (name, description, category, etc.).
3. Uploading AABfile and other materials (screenshots, banners).
4. Indicating the target audience and content classification.
5. Setting the price (free or paid).
6. Submitting for moderation (can take from several hours to several days).

⚠️ Attention: Publishing rules c Google Play are regularly updated. Before submitting, check the latest requirements for content, permissions and privacy policy on official website.

FAQ: Frequently asked questions about development in Python for Android