Web playground for iOS

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Phosphor Screenshot

Phosphor provides a live updating web environment to play around with web technologies on iOS with zero friction. Phosphor features a native text editor with syntax highlighting for HTML, CSS, and JavaScript. As you type, the web preview will be updated automatically.

Phosphor is under active development and in beta testing. I'd love for you to test it out! Download the beta from TestFlight and follow me on Twitter for updates. Email me with questions/feedback.

Phosphor Editor Screenshot
A Processing sketch using the bundled Processing template with p5.js

Text Editor

Beautiful, native text editor with tabs for each type of content. Perfect for everything from quick explorations in Processing to prototyping complete web pages (like this one).

Phosphor Screenshot
The basic template splits code into HTML, CSS, and JS tabs. I prototyped this site there.
Phosphor Screenshot
Hide the web preview when you need to focus on your code. You can also hide the editor to focus on the preview

Code wherever you are

Come across an interesting tweet about a technique while scrolling Twitter? Open up Phosphor side-by-side and you can be exploring in seconds

Phosphor Twitter Screenshot
Works in split view so you can code while you have another app open


You can start from a number of pre-defined templates. Custom templates are planned for the future so you can setup your boilerplate once and never again

Phosphor / New File


JavaScript errors show natively and give you the line with the error. There's also a console for viewing logs and debugging


Screencast of Phosphor in action on an iPad Pro, using the Processing template and exploring some code from the web

Note: some of these screenshots/videos are out-of-date. I've been making frequent changes and haven't had a chance to update them. Download the beta to see it for your self!

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