# Running on smartphone


You should know that the game works on a smartphone. But for a good user experience, several criteria must be met

  1. The game must be Responsive Design. Depending on the size of the screen, the game remains playable.
  2. We have controls to make the character move or do an action.
  3. The game can be installed on the smartphone and can be played offline (in the case of an RPG).

# Responsive Design

the notion of Responsive is done with CSS. Here is a complete example of an HTML page:

<!doctype html>

    <meta charset="utf-8">
    <title>RPG Game</title>
    <meta name="viewport" content="initial-scale=1, maximum-scale=1, user-scalable=no, minimum-scale=1, width=device-width, height=device-height">

    <div id="rpg"></div>
        html {
            height: 100%;
            overflow: hidden;

        body {
            margin: 0;
            background-color: black; 
            display: flex;
            align-items: center;
            justify-content: center;

        #rpg {
            position: relative;   

        @media (min-width: 800px) {
            #rpg {
                width: 816px;
                height: 624px;

        @media (max-width: 800px) {
            #rpg {
                position: absolute;
                top: 0;
                left: 0;
                right: 0;
                bottom: 0;


Note that the Canvas and the GUIs all take the size of the main selector (#rpg)

# Controls

To put controls (as in the picture above), you have to create a GUI and open it as soon as the card is ready. You are free to create a GUI named rpg-controls. Then, you can inject rpgScene into the component and take advantage of the applyControl() method to apply controls when a GUI location is pressed.

If you don't want to create by yourself, You can add the plugin for the mobile

npm install @rpgjs/mobile-gui

In src/modules/index.ts

import mobileGui from '@rpgjs/mobile-gui'

export default [
    // other modules and ...

As soon as the map is opened, display the GUI for controls

# Offline Mode

Works only when building the game and not during development

The notion of offline mode is already integrated in RPGJS. Files are cached for offline play and a PWA is created to install the game on smartphone. To do this, create an rpg.json file at the root of your project.


    "name": "My Game",
    "short_name": "Game",
    "description": "Beautiful Game",
    "background_color": "#ffffff",
    "icons": [
            "src": "icon.png",
            "sizes": [96, 128, 192, 256]

The properties are the same as the Webpack PWA Manifest (opens new window) module.