The Timeline

The activity of your Partners and Rivals is displayed on this screen, and you can spectate battles and send out Nices from here. Your activity is also displayed for Partners and Rivals to see, and they can spectate and send you Nices! You can show your Status on the Timeline by tapping "Request."

Choose "Request Tag Partner" to tell your Partners you want to tag up.
Choose "Request Opponent" to tell your Partners and Rivals that you want to battle!