YouTube Go is one of the apps thats part of Googles effort to get the same information to people in developing countries while using a lot less data. There are other apps with the same concept: a lightweight version of an otherwise data-hungry app that offers the apps core functionalities while keeping tabs on data usage.
The app is expanding to 130 countries around the world, so its quite a big deal. The app is arriving in the Play Store in many countries in Central and South America, Middle Eastern countries, and part of Africa. YouTube Go first launched as a Beta product in India before officially releasing in Indonesia.
Mobile internet is still considered a luxury in many parts of the world, so YouTube Go is meant to let people download YouTube videos to their internal storage where theres good reception or a Wi-Fi network available. Users can then watch these videos whenever they want to, and YouTube Go even lets these users share videos with others without the need for an internet connection.
Similar to how Files Go sends files: if you wanted to send a video, youd select it from the videos saved on the device and the person youre sending the videos to would have to open the YouTube Go app and hit receive. This works sort of like airdrop in that the phones use Bluetooth to detect and handshake with another nearby device, then Wi-Fi direct takes over and transfers the videos.
In the past, you could only send one video at a time, but the YouTube Go app has been updated to be able to send multiple videos in one go. Of course, in order to play the video on a new device, YouTube Go needs to make a quick communication with its servers to download a decryption key. This is a precaution to keep developers from abusing the download feature.
YouTube Go on the Play Store