Isolating iPad viewport from other mobile devices

The site: undrln

I’m forcing the viewport for mobile devices by the commonly-known meta tag approach:

<meta name="viewport" content="width=device-width, initial-scale=1" />

The problem is that the iPad is also affected by this and by default zooms in too much. If I remove said meta tag then the iPad version looks as intended, but then mobile users are screwed (especially non-iPhone/iPod Touch users).

I’m trying to stay true to “progressive enhancement” without resorting to UA sniffing, but I’m running out of ideas.

Any thoughts?