Pinterst Lens (beta) is a new content discovery tool the company is experimenting with Right now it's working best with home decor ideas, but i'm sure Pinterest will be moving that into other topics as it learns.
It's also got Instant Ideas which works on the same principle.

The Shop the Look facility, launched just over a year ago, has also expanded to additional brands.

Clearly, as Pinterest puts it, it's

It’s called Lens (currently in beta), and it lets you use the camera in your Pinterest app to discover ideas inspired by objects you see out in the real world. Pinterest Introduces Lens (Beta) Search Discovery Tool [blog.pinterest.com]

Just point Lens at a pair of shoes, then tap to see related styles or even ideas for what else to wear them with.

Instant Ideas and Shop the Look are available now on iPhone, Android and the web. Lens will be rolling out in the US over the coming weeks—look for it on your iPhone or Android app soon!