iPad format output in print mode ?

Is there a format that matches the iPad screen (I have iPad air 2 but I guess I am not the only one to use such a tablet to read scores…) already in the presets ? I could not find it, and I had to create my size of page ; I think it would gain some time to have it already there.
[edit] I find the ratio of “Part (9,5"x12,5”) would be the closest to my iPad screen. Is it on purpose ? I would love to have all those lengths in mm — meter is the only universal unit for the scientific field nowadays…

Do you realize you can set measurements in millimeters in the General Preferences under the Edit menu?

Yes, Derrek. I think it is the very first thing I have done after installing Dorico, on day 1. Preferences/Général/Unité de mesure préférée : mm.
I guess it is a bug, then, because I still have inches showing up everywhere. Well, ok, it 's a bug. Thank you for making it clear !

The ‘Preferred units of measurement’ preference is only used in a couple of places at the moment, specifically on the Page Setup page of Layout Options. All of Dorico’s measurements at the moment are in points, which is not the same as inches, of course (though 1pt = 1/72"), and at least for now you can only actually enter values in points. We hope to make it possible to type values in any format, provided you specify the unit, e.g. 0.5cm or 1pt or 3/4" or 0.25" etc., in future.

Daniel, thanks to you, I discover that 1 point = 0,352778mm. I am looking forward to this possibility to specify units, as I do on every XeLaTeX document I produce. This is so confortable !