---
lang: en-GB
---

# Set up mobile

This tutorial will help you to set up your development environment, use a dev build and create an APK.

## Table of Contents
* [Environment](#environment) : Dependencies, packages, app key, device and .env
* [Dev build](#dev-build) : Create, install and use
* [APK](#apk) : Create and install

## Environment

### .env files

Some infos like API keys or IP addresses cannot be pushed on the public repository, therefore you have to create the .env files that will store those values. Go in the `traque-app` folder, create those two files and replace the FILL_HERE with the correct values (you can ask someone already working on the project) : 

* `.env.development` :

```.env
EXPO_PUBLIC_SERVER_URL=FILL_HERE
EXPO_PUBLIC_SOCKET_URL=FILL_HERE
```

* `.env.production` :

```.env
EXPO_PUBLIC_SERVER_URL=FILL_HERE
EXPO_PUBLIC_SOCKET_URL=FILL_HERE
```

### Installing dependencies and preparing the device

You will need to install Android Studio, some SDKs and prepare your device if you want to use a physical one. Follow this [tutorial](https://reactnative.dev/docs/set-up-your-environment?os=linux&platform=android).

Note : if you want to use a physical android device, you just have to follow the first part of the tutorial. You may also enable install via USB depending on your device.

### Installing packages and create the android folder

Go in the `traque-app` folder and run `npm i` to intall the packages of the project.

Then run `npx expo prebuild --platform android` to create the android folder needed to create a dev build or an apk.

In order to prevent an issue, go to the `android/build.gradle` file and replace the line `classpath('org.jetbrains.kotlin:kotlin-gradle-plugin')` by `classpath('org.jetbrains.kotlin:kotlin-gradle-plugin:1.9.25')`.

In order to be able to have a dev build and an apk on the same device, go to the `android/app/build.gradle` file and add :

```txt
android {
    ...
    buildTypes {
        debug {
            ...
            applicationIdSuffix ".debug"
            versionNameSuffix "-debug"
        }
        ...
    }
    ...
}
```

### App key

An app key is like a signature of the application and is required by google play store. Therefore, you can skip this part if you don't plan to publish your modifications on the Google Playstore.

#### Create the app key

An app cannot have more than one key associated to it. If a key have already been generated for this project, please contact the creator of the key and follow to the next section.

Go in the `traque-app/android/app/` folder and run `keytool -genkey -v -keystore release.keystore -alias traque_key -keyalg RSA -keysize 2048 -validity 10000`.

Note : `release` and `traque_key` can be modified if you want.

#### Add the app key

Put the `.keystore` file associated with your app into `traque-app/android/app/` and then modify the android bracket of the `traque-app/android/app/build.gradle` file as follows :

```txt
android {
    ...
    signingConfigs {
        ...
        release {
            storeFile file('TO_BE_FILLED.keystore')
            storePassword 'TO_BE_FILLED'
            keyAlias 'TO_BE_FILLED'
            keyPassword 'TO_BE_FILLED'
        }
    }
    buildTypes {
        ...
        release {
            ...
            signingConfig signingConfigs.release
        }
    }
    ...
}
```

## Dev build

A development build (or dev build) is an application that can be installed on you device, that connects to a development server and that allow you to see the modifications instantly.

### Build and install the dev build

Here you need to connect your device to your computer with a USB cable.

Go in the `traque-app` folder and run `npx expo run:android` in order to build the app and send it on your device.

### Use the dev build

Here you can work over USB or over the wifi.

Go in the `traque-app` folder and run `npm start` to start the development server. Verify that a blue *development build* appears in your terminal. Then scan the QR code that appears with your android device.

Note : if the app crashes, you may need to restart the development server.


## APK

An apk is an application that can be installed on an android device without the need of google play store. It is a definitive version of your application that can't be modified after being built.

### Build the APK

Go in the `traque-app/android/` folder and run `./gradlew assembleRelease`. At the end, the created apk will be located in the `app/build/outputs/apk/release/` folder.

Note : if the build fail you may try to delete and recreate `node_modules/` or `android/`, you may also try to delete the `~/.gradle/caches/` folder.

### Install the APK

Simply share the APK with a drive and click on the APK file on your device to install it.