Android Shop project · Free · One Python file

Kotlin files in. Android app out.

android_scaffold turns a folder of Kotlin and Jetpack Compose files into a running Android app with one command. No Android Studio, no Gradle setup, no XML. It builds the APK, boots the emulator, installs your app and reloads it every time you save.

Quick start Download the script Small-screen guide

python3 android_scaffold.py my-app --name "My App" --watch

Thumb zone

Get the script

android_scaffold is a single Python file with no dependencies outside the standard library. Download it and run it with Python 3.8 or newer.

curl -LO https://android-shop.github.io/android_scaffold.py
python3 android_scaffold.py my-app --run

wget https://android-shop.github.io/android_scaffold.py
python3 android_scaffold.py my-app --run

Write the app. Skip the project.

Even a one-button Android app normally needs about 12 files and 220 lines of Gradle, XML and properties before your code can run. android_scaffold writes all of that for you, from nothing but your .kt files.

One file, one command

Put a Compose Activity in a folder. That is the whole project.

package com.example.tapcounter

import android.os.Bundle
import androidx.activity.ComponentActivity
import androidx.activity.compose.setContent
import androidx.compose.material3.Button
import androidx.compose.material3.Text
import androidx.compose.runtime.getValue
import androidx.compose.runtime.mutableIntStateOf
import androidx.compose.runtime.remember
import androidx.compose.runtime.setValue

class MainActivity : ComponentActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContent {
            var taps by remember { mutableIntStateOf(0) }
            Button(onClick = { taps++ }) { Text("Tapped $taps times") }
        }
    }
}

python3 android_scaffold.py tap-counter --name "Tap Counter" --run

That generates the project, builds a debug APK, boots an emulator (or uses the phone you plugged in), installs and opens the app, and copies the APK to apk/ so you can send it to anyone. Walk through it step by step.

Everything between your code and the phone

The script handles the setup that usually stops a quick idea from getting built.

A live prototyping loop

Run with --watch and the emulator becomes your preview window. Save, and the app relaunches with your change in a few seconds.

[*] Watching 'tap-counter' for Kotlin changes. Press Ctrl+C to stop.

[*] Changed: MainActivity.kt
[+] Reloaded in 2.8s. Watching for changes...

Compile errors are printed and watching continues, so you fix and save again. How live reload works.

Build for the device in your pocket

Once setup costs nothing, it's worth building small apps that work one-handed, offline and out in the field. The Android Shop small-screen guide shows how, from the thumb zone to offline-first storage.

See it in a real app: Thumb Inventory

The repository ships a complete example built with the same one-line command: a one-thumb stock counter for shelves, fridges and stockrooms. Big tap targets, swipe and long-press, haptics with undo, offline storage and CSV sharing.

Read the walkthrough

Frequently asked questions