IceCat is the GNU version of the Firefox browser, with most, if not all, of the features that Firefox comes loaded with. The difference is that it is entirely free software. Whilst the Firefox source code from the Mozilla project is free software, they distribute and recommend non-free software as plug-ins and addons.

Key Privacy-Protection Features include:

• LibreJS: GNU LibreJS aims to address the JavaScript problem described in Richard Stallman's article The JavaScript Trap.
• HTTPS-Everywhere: Extension that encrypts your communications with many major websites, making your browsing more secure.
• SpyBlock: Blocks privacy trackers while in normal browsing mode, and all third party requests when in private browsing mode,(Based on Adblock Plus).
• AboutIceCat: Adds a custom "about:icecat" homepage with links to info regarding the free software and privacy features in IceCat.
• Fingerprinting Countermeasures: Fingerprinting is a series of techniques allowing to uniquely identify a browser based on specific characterisics of that particular instance.

IceCat has several integrated security add-ons which come as standard. The extensions are designed to increase the stability of the browser, by blocking privacy trackers on any website you visit, and managing JavaScript pages. The other plug-ins can replace online video players with the Firefox native player and automatically use HTTPS rules also.

As IceCat is a fairly standard browser there are no real surprises. It has a reliable, familiar environment for browsing; it supports tabbed browsing, private browsing sessions, saving the current page as HTML or printing them. Browsing history and bookmark creation remains the same as in Firefox.

Overall, IceCat provides you with a reliable, secure environment for visiting your favorite websites. As the app is built on the same kernel as Mozilla Firefox it resembles it considerably in both functionality and interface.

Requirements: Intel, 64-bit processor and OS X 10.6 or later.