The CTL NL61, NL61T, J5, J2, J4, J4+ and the X-Panel variations will all support Android Apps. Google hasn't released the exact date but it is expected in Q1 of 2017.
This is the complete list of Chromebooks from Google:
CTL Chromebook J2 / J4
N6 Education Chromebook
J5 Convertible Chromebook
How to Side Load an App (APK) on a Chromebook - Link
Popular location to get APKs **use at your own risk** http://www.apkmirror.com/