Good morning. We've had some robust conversations in our office regarding possible drags on system time caused by use of web fonts on our mobile websites. One of our product leads is lobbying heavily for strict use of "system fonts" on mobile devices. By system fonts, he's referring to San Francisco (iOS) and Roboto (Android). Perhaps best way for me to ask my question is to state how this works and ask you kind people to savage me where I am incorrect. OK? Here's how I think this works.
-- San Fran and Roboto are natively installed on iOS and Android devices.
-- Although San Fran and Roboto are system fonts, they are not browser default fonts. Browser defaults are Arial, Helvetica, etc.
-- If I use San Fran or Roboto in my mobile web design, I call it in my CSS, as I would with any web font. The difference is that the native font is preloaded. So I don't have any millisecond lag while I load a web font that is not native to the device.
-- If I load a web font, a user experiences a slight lag (milliseconds) on first load. After that, the font is cached, so there is little or no difference in load time between the native font and web font on subsequent site visits.
-- Because native fonts are not browser defaults, there is still a FOUT possibility, although a bit smaller chance perhaps.
Am I close? Any help appreciated. Thank you.