Pinterest is totally not transferable to small screen mobile devices. Its main point is to offer many images at a glance, which is impossible on small screen.
Wow, and I always thought Pinterest was a smartphone app like Instagram. (Not interested in it so I never bothered checking)
There is a Pinterest iOS app but the web site is definitely the preferred way of using it. The phone app attempts to look like the web site but the layout doesn't transfer to the tiny iPhone screen very well and is not very nice to use because of this.
You should really check out Pinterest even if you aren't interested in the content -- the UI they have created is very slick and interesting.
I encourage you to check out DRIFT[1]. You can browse the latest images for inspiration (á la Pinterest), and its responsive design scales from large-screen TVs to the smallest handheld devices.