Is there anyway for this to work on IOS?
It appears that none of the fonts in the list are the fonts used on IOS. Is that intentional?

When you call font-family: system-ui and you've used @font-face { font-family: system-ui; }, does that override the new browser standard system-ui? Would that mean, ignore this new generic system-ui (https://www.chromestatus.com/feature/5640395337760768) and use my font-face stack. Or does it mean, use the new generic system-ui and if that's not understood by the browser, run through this list of fonts in the font-face stack?

I'm finding this really hard to describe, sorry :(

Or to cover IOS with these font-face declarations should we just use something like font-family: system-ui, sans-serif.