Mozilla boss Jay Sullivan made the remarks at a panel at digital and music festival South by Southwest in Texas, saying that there were no plans to build an iOS browser despite the popularity of Apple devices.
Firefox uses the Gecko rendering engine, while Safari and rivals such as Chrome use WebKit.
Apple's Safari browser is the default app for web surfing, and even if you install a rival app like Chrome, you can't change that default setting. That means links in other apps automatically open in Safari. As a result, Safari has more than half of the mobile browser market.
Mozilla is taking on mobiles in another way: Firefox OS. Firefox OS is an open source HTML5 operating system designed for manufacturers and networks to put in low-cost phones as an alternative to Android. The idea is to divert the flow of app money going from their phones to Google, so it ends up in their pockets.
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