Mozilla is currently finalizing Firefox for iOS, this can be made up from its Github repository. The browser seems to use Apple's Webkit engine instead of Mozilla's own Gecko engine. Mozilla plans to start a marketing campaign to promote the browser in which it will try to differentiate from Chrome and Internet Explorer by emphasizing on the privacy features of the browser.
The marketing campaign is needed because, according to Mozilla, there is an alarming trend of a decreasing market share of Firefox. The browser, that 10 year ago was introduced as the first Internet Explorer 6 alternative, loses many users to Google's Chrome browser.
It was already known that Mozilla was working on Firefox for iOS but it was unclear when the browser would be released. Mozilla previously released Firefox Home for iOS but that was no full fledged browser.
The Github repository also contains some concept images which show how the browser will look on Apple's mobile operating system.
