Yep - they're Apple for credit card processing. All they do is UX work and strip out features.
That's a great thing. My wife and I own a small boutique, and we've been using Square since before the public launch in the App Store. We've just about outgrown it, but have been challenged to find another solution that fits in-between the low cost, extremely easy to use Square and the traditional high-cost, complex to set up POS solutions.
As one of their employees here has said, GoPago seems to fit that nicely, but we're not decided yet whether we want to commit to a $100 / month payment. Being a hacker, there's also the fact that I have a room full of hardware in the back I've collected over the years, which includes a nice flash-based small format PC, a comparably tiny monitor, bar code readers, and a couple of retail thermal printers.
I know I'll never actually sit down and hack out a POS system, but it's nice to think about and the idea has helped in keeping me from sinking a wad of cash into a system I don't absolutely have to have yet.