📱 Build a Kotlin Android App with Flask REST API – Full Integration Guide

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🔧 What We’ll Build

We’ll create:

• A Flask-based REST API that handles TODO tasks (GET, POST, DELETE)

• A Kotlin Android App with Jetpack Compose UI

• Integration using Retrofit for networkingWrite your text here...

🧩 Technologies Used

• Backend: Python 3.10, Flask

• Frontend: Kotlin, Jetpack Compose, Retrofit

• Tools: Android Studio, Postman (for testing), Emulator/Device

🚀 Part 1: Build the Flask REST API

Step 1: Set Up Project Folder

Step 2: Install Flask & Setup API

Create requirements.txt:

Then create app.py:

Create todos.json:

Step 3: Run the Flask Server

🤖 Part 2: Build the Kotlin Android App

Step 1: Create a New Project in Android Studio

• Select Empty Compose Activity

• Name: TodoFlaskApp

• Language: Kotlin

• Minimum SDK: API 21 or higher

Step 2: Add Retrofit & Compose Dependencies

Edit build.gradle (Module: app):

Sync Gradle.

Step 3: Create Models

Create Todo.kt:

Step 4: Retrofit API Interface

Create TodoApi.kt:

Step 5: Create Retrofit Client

Create RetrofitClient.kt:

Step 6: MainActivity with Jetpack Compose UI

Replace MainActivity.kt with:

🧪 Testing

• Run the Flask app: python app.py

• Launch Android Emulator

• Run the Kotlin app

• Add and delete todos – changes will reflect instantly!