If anyone was hoping to buy the Samsung Dex to use with their Galaxy and Logos, don't bother. The app won't go wide screen so it's pretty ordinary experience. I'm hoping by posting this that someone at Logos will turn on a switch to make it work, but I'm not holding my breath since it's such an obscure feature/device that not many will have.
BTW it does go full screen on a Chromebook with Google Play, so I guess its possible.