Cross Copy - Simple cross platform media sharing

At it's core, Cross Copy provides a simple way to avoid having to email links, text, and files to yourself. It works in a similar way to Google Drive or Dropbox, but without the bloat of folders, subscriptions, or size limits.

As with most of my projects, I built Cross Copy to overcome a common problem that I encountered at work. Part of my previous job was to create and deliver weekly (sometimes daily) reports which included photos of the work that had been completed on a job-site. Since I was using an iPhone, and my work computer was a Windows, I used to simply email the photos to myself. However, the 20MB limit on emails is quite limiting when each photo is 6MB+ each. Additionally, sending files/photo/url links from my personal Mac to my work PC was a pain.

This is obviously not a new problem, and there are dozens if not hundreds of solutions out there already, most of which are better than Cross Copy and offer more features. I decided to build it myself, 1. because I wanted to see if I could do it, and 2. because I found using common services like Google Drive or Dropbox to be cumbersome, with honestly too many features.

Cross Copy is the simplest service I have come across, a basic interface that works well on mobile and desktop, no storage or folders (files are automatically deleted after 7 days), and no account/subscription required. I even built a Chrome extension which means you don't even have to open the webpage to access your files.

The system is broken up into 3 parts:

• The Main Web App — Transfer text, photos, and files directly in the browser from any device.

• The Mobile Application - Allows you to share photos and files natively from your mobile device to Cross Copy.

• The Chrome Extension — Instantly access copied text, files, and photos right from the Chrome toolbar.

It uses Firebase Authentication, Storage, and Firestore, which are accessed directly on the client side using carefully set rules. All of the source code is available on my GitHub.

The main web app

The easiest way to use the service is to simply open the website crosscopy.dev in a browser. Users can either choose to create an account, or continue anonymously with a linking code. They're then taken to the main homepage as seen below where they can paste text or add files.

Anything added to the homepage is instantly synced to their account, and is available in the browser, app, and chrome extension on any device. There is no compression or restriction on what kind of file can be transferred which is great when you need full resolution images.

The text section of the application supports instant sharing of rich-text between devices. Any text that is typed or pasted into the window retains it's content, styling, and media.

Additionally, anything pasted will be stored in the History tab, so you'll never lose another link again.

The Mobile App

The mobile application is built using React Native Expo with some native libraries to provide additional tools. For example react-native-receive-sharing-intent creates a sharing target so users can share photos and files directly to the app. It also uses

react-native-document-scanner-plugin to quickly generate PDF documents from the camera. Whenever I need to scan a document (copies of licenses, passports, etc.) I almost always use Cross Copy.

The Demo above shows a photo being shared to the Cross Copy app, which is then uploaded to the users cloud storage, and can be accessed from their browser almost immediately.

Both the mobile and web applications also support peer-to-peer sharing, so users can quickly share photos and files with each other directly via QR code or link - without requiring an account.

Mobile to desktop browser sharing currently works seamlessly, however I'm still sorting out some issues with the application before I release it publicly.

The Chrome Extension

The Cross Copy Chrome extension is essentially a lightweight version of the main web application. It’s designed for users who want fast access to their copied files, links, and text directly from their browser, without needing to open a new tab or visit the website. Once installed, the extension sits quietly in the Chrome toolbar, ready to open with a single click.

Just like the main web app, the extension supports both anonymous and authenticated access. Users can link their browser session with the mobile app or another browser via a simple 4-character code, and anything copied or uploaded to their account becomes instantly accessible. It syncs in real-time, meaning files added from your phone will appear in the extension within seconds—no refresh required.

I use the extension most often when I'm on my work laptop and need to quickly grab something I copied earlier on my phone—whether that’s a file, a block of text, or a Google Maps link. Instead of emailing myself or digging through AirDrop or cloud folders, I can just click the Cross Copy icon and it’s all there.

The extension was a fun challenge to build, as it required adapting the entire Cross Copy experience into a compact UI that still felt intuitive and powerful. It supports drag and drop file uploads, and it's perfect for reading, copying, or downloading your recent items. For most daily use-cases, it’s the fastest way to get content from your phone to your browser, or vice versa.

You can visit the Cross Copy Extension in the webstore here.