What device is this? I've seen a particular phone on Engadget and many other sites but I can't figure out what it actually is.

Here is a link: https://www.engadget.com/2016/05/22/google-science-journal-for-android/

Any ideas?
If you're talking about the one in the title picture, it's obviously an LG V10, specifically the dark blue color variant. The signature "secondary screen" is present.