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Duo free download for Mac


Version 1.3

Dual-paned web browser to display 'desktop' and 'mobile' view.

Duo overview

Duo is a dual-paned web browser that lets you browse the web in two views: your standard ‘desktop’ view as well as a typical ‘mobile’ view. By seeing these two views at the same time, you’re able to quickly test and work through multiple screen experiences rather than considering them separately.

Whether you’re a designer or a developer, project manager or client, Duo gives you a new tool to make your Responsive Web Design project go more smoothly than ever.

Get the bookmarklet: http://helloduo.com


  • Fixed mobile view: Duo gives you a typical ‘mobile’ view using a fixed-width pane.
  • Tablet / desktop view: In your second pane, browse the web using any width you’d like.
  • Synchronized browsing: Navigating in either pane updates the other. No need to reload layouts to view pages at different sizes.
  • Webkit dev tools included: Duo has everything you need to make sure your design is doing what it should. Debug code in either pane.
  • Convenient key commands: Duo includes tools for clearing your cache and getting rid of those pesky cookies via standard key commands.
  • Handy bookmarklet: Use the convenient bookmarklet in your other browsers to push a site over to Duo.

What’s new in version 1.3

Updated on Jul 29 2014

Version 1.3:
  • LiveReload support





1.7 MB

Developer’s website




App requirements

  • Intel 64
  • OS X 10.8 or later
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Jul 29 2014
Jul 29 2014
Version: 1.3
They seriously need to offer a demo. As a web designer, I know, simply shrinking the viewport of your browser does NOT produce results identical to your mobile device. I use the iOS Simulator that comes with Apple's Dev Tools all the time. It seems to be the only truly accurate representation of what your design will look like on iPhone/iPad. Having said that, switching back and forth is pain. If Duo even came close to being accurate, it could be worth it.
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