We asked YouTube what exactly it has changed between then and now. Team management In Mobile is Who for up chatting your app as a team without sacrificing security. Want to watch a video together with your friends simultaneously? Real-time data failover Keep your messages flowing without missing a beat. In other words, you have to invite them using any of the existing ways you already rely on to share videos. It will automatically populate your contacts, but you can also add a contact, or allow someone to add you as a contact, by scanning a in Mobile is Who for up chatting code. You can even start a secret conversation which is end-to-end encrypted. This makes it an ideal way to chat with friends and family, particularly for group video chat. Ship Faster Cut development effort. Cross-platform SDKs Easily port the same app to different platforms.