If you searching for icons for your app or website, check out http://modernuiicons.com/. There are over 1000 icons designed for your app or website. It is a very good library when building modern UI apps for Windows Phone, Windows 8 or iOS7. But I have also used them for different websites. When I searching for icons I almost always finds an icon in Modern UI icons library.
When you download the library you will get a dark and a white version of the icon. But you also got them in the vector format, .design and .svg.