Apple has been using the same typeface for all its’ iPod products for years now, and it seems they’ve carried this same marketing over to the iPhone.

To replicate exactly what this looks like, for any personal reasons, simply use the font Myriad Pro, Semibold, at its’ default kerning.

You can notice by my image comparison that the official logo seems to be a modified version of Myriad Pro, somewhat elongated on the height scale. This is especially noticeable in the “o.”