Just got my Go in July 2018, but for those who need the answer I offer this.
Pair the Oculus app on the phone with Go and use setting to enable developer mode. When USB is connected the Go will appear as VR Headset device with internal storage at top level.
I find BETA Skybox extremely adept at making most VR360 including 3D from Youtubes viewable. Oculus TV and Samsung TV are also good viewers.
The hard way to do it is as follows. I also sideloaded ES File Explorer and the Snapbridge 360 app on the Go but that is a difficult and time consuming way but eliminates need for computer or cellphone for transfers from camera. Also used Oculus TV to find and run flat screen app - ES File Explorer and then ES is able to find apk's for installing. ES File Explorer is also needed to find and run the Snapbridge app.
System 76 Lemur | 14.1 ′′ Matte 1080p IPS LED | laptop w/ factory mods Intel Core i7-6500U CPU @ 2.50GHz | 8 GB DDR3 at 1600 MHz 250 GB M.2 SSD | WiFi 867 Mbps Favoring Open Source -> Ubuntu Studio 18.10 for Nikon Keymission 360 & Web VR to Oculus Go