Comment by chriswarbo

Seems a bit weird to use Skype as your example, since (a) it already had a native application for Linux, (b) AFAIK it was the same (Qt) codebase as Windows and Mac, so no feature discrepancy, and (c) Skype also developed clients for other operating systems like Symbian, Android, Blackberry, etc. as well as a Java-based client for other mobiles.

If anything, it's easier to develop cross-platform native applications these days, since the mobile space has mostly collapsed to just Android + iOS.