What setting(s) are you trying to change? The version of Firefox for iOS is very "stripped down" compared with Firefox for Windows, and also mobile browsers often use different approaches for accessing settings, so in order to guide you to the right place (or to let you know if it even exists), it would be helpful to know what you're trying to do. More generally, on Firefox for iOS, you can get to the Settings dialog as follows: * tap the tabs icon on the address bar (shows the number of tabs currently open) * at the upper left of the tab thumbnails page, you will find the gear/wheel icon