explaingit

responsively-org/responsively-app

★ 24,933TypeScriptAudience · developerComplexity · 2/5MaintainedLicenseSetup · easy

TLDR

Desktop browser for web developers that shows how websites look on multiple device sizes simultaneously, with mirrored interactions so you test all screens at once.

Mindmap

mindmap
  root((repo))
    What it does
      Multi-device preview
      Mirrored interactions
      Hot reloading
      Screenshot all devices
    Key features
      30+ device profiles
      Custom devices
      Element inspector
      Browser extension
    Use cases
      Test responsive design
      Verify layouts
      Check user flows
      Debug across sizes
    Tech stack
      Electron
      TypeScript
      Desktop app
    Audience
      Front-end developers
      Web designers
      QA testers

Things people build with this

USE CASE 1

Test how a website looks on iPhones, tablets, and desktops all at the same time without resizing your browser repeatedly.

USE CASE 2

Verify that a responsive design works correctly across 30+ real device profiles with a single click.

USE CASE 3

Debug layout issues by inspecting elements and seeing changes reflected instantly across all device previews.

USE CASE 4

Take screenshots of your website on every device size at once to share with your team or client.

Tech stack

TypeScriptElectronReactNode.js

Getting it running

Difficulty · easy Time to first run · 5min
Use freely for any purpose, including commercial use, as long as you keep the copyright notice and license text.

In plain English

Responsively App is a desktop browser built specifically for web developers who need to test how their websites look across different screen sizes, phones, tablets, laptops, and desktops, all at the same time. Normally, testing responsive design (designing websites that adapt to different screen widths) means repeatedly resizing your browser window or using browser developer tools to simulate different devices one at a time. Responsively shows multiple device previews simultaneously in a single window. The key feature is mirrored interactions: when you click, scroll, or type in one device preview, all the others do the same thing simultaneously, so you can test a user flow across all screen sizes without repeating every action multiple times. It comes with 30+ built-in device profiles (iPhone, iPad, various Android phones, etc.) and lets you add custom ones. There's a shared element inspector across all devices, one-click screenshots of all previews at once, and hot reloading (the page updates automatically as you change your code). A companion browser extension for Chrome, Firefox, and Edge lets you send URLs from your regular browser directly to the app. You'd use this during front-end web development whenever you need to ensure a page or component looks right on multiple screen sizes. It's free, built with Electron (a framework for building desktop apps with web technologies), and available for Mac, Windows, and Linux.

Copy-paste prompts

Prompt 1
How do I set up Responsively App to test my React website on iPhone and iPad simultaneously?
Prompt 2
Show me how to add a custom device profile to Responsively App for a specific screen size I need to test.
Prompt 3
How do I use the Responsively browser extension to send a URL from Chrome directly to the app?
Prompt 4
What's the fastest way to take screenshots of my website on all device sizes at once using Responsively?
Prompt 5
How do I enable hot reloading in Responsively App so my changes appear instantly across all device previews?
Open on GitHub → Explain another repo

Generated 2026-05-18 · Model: sonnet-4-6 · Verify against the repo before relying on details.