How to use polymer to build a menu that looks like the "Google App Switcher"?

[jennyxi...@gmail.com]

I am trying to build an element that looks like the "Google App" switcher that shows in the up-right corner of google main page. Please see below, after clicking on the icon, a menu shows up which enables you to lay apps in a row of 3. I tried using paper-menu, but it does not allow me to put 3 apps in a row, it only shows one app each row(like a list). I am really struggling with this, anyone who knows, please help.