File picker on Nexus 5, Android 4.4.4

[AC Question]

I've read that Nexus 5 has a File Picker. How do I access it?

 

[mrsmumbles]

I'm not sure but I think that refers to the ui we see when we want to attach a file to an email or text, or upload to Drive, or work with files in QuickOffice. There's a YouTube on it, but I didn't watch it.

This is a picture of what I think file picker is