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Firefox for iOS

For more and more people mobile devices are the primary way, or even the only way, to access the Web. Firefox for iOS (codenamed Fennec like its Android counterpart) is an open, hackable, standards-based browser, just like the desktop Firefox.

Firefox for iOS constructs its user interface from native widgets instead of XUL; this greatly improves performance, especially startup time, and memory consumption. Because of Apple's App Store restrictions, it also uses the built‑in iOS WKWebView, which is based on WebKit rather than Gecko.

Contribute to Firefox for iOS

We're hard at work building Firefox for iOS, and we welcome your help! The main starting point for anyone interested in contributing to the Firefox for iOS project is the GitHub page.

You can help us to create and improve Firefox for iOS:

It is now possible to change the default browser on iOS starting from iOS 14. For users using an older version of iOS, they will have to resort to copy-paste tricks. If you are targeting below iOS 14, there are some things you can do in your native apps to make these users happy:

  • Make the iOS App extensions system available to your users. Firefox for iOS provides some app extensions that make opening, bookmarking, and adding to the Firefox Reading List possible from your app. nshipster has a good overview on how to add a UIActivityViewController to you app.
  • Use the Open-In-Firefox SDK to easily detect if Firefox is installed and show it as an option for your users. In future releases, this will also make it easy for users to return to your app after reading an article in Firefox.


Firefox for iOS supports the native iOS extension ecosystem right now, but doesn't (yet) support JavaScript add-ons like Desktop or Android Firefox.

There is ongoing work to get Lightweight themes to work in bug 1210119 and WebExtension‑based themes in bug 1466496.

Get help

Documentation and tutorials for using and troubleshooting Firefox for iOS are available on the Mozilla Support website.