The TV app gathers TV shows and movies from a variety of providers, including Hulu, Amazon Prime Video, ESPN and Apple's own iTunes, and provides a single place to browse and find new stuff to watch. An update in March brought so-called "channels" including HBO, Showtime and more, which let you subscribe and watch from within the TV app itself. Thewill also live in the TV app when it becomes available this fall. Note that Netflix itself is not available in the TV app.
At WWDC Apple CEO Tim Cook demonstrated a panel that opens up on one side of the screen and allows different family members to show their own content. The changes are reflected in "Up Next," the top line of the Apple TV app.
Cook also announced that the Apple Music app for Apple TV would get multi-user support, so different family members would also get different lists of songs. He also showed lyrics on the TV screen and claimed that the Apple Music app on Apple TV provides "best music experience on television."
Cook also announced new screensavers for the Apple TV, including underwater scenes.
Multi-user support was only announced for the TV and Apple Music apps as part of the TVOS operating system for Apple TV, not for those same apps on iPad or the iPhone.