Go to Data and choose Records, then choose Brawl Records. Now you will see many things here:
- Power Time, which means how much time you had the game on
- Solo Time, which means how much time was spent in the Solo mode
- Group Time, which means how much time was spent in the Group mode
- Online Time with Anyone, which means how much time was spent during "With Anyone" matches on Wifi
- Online Time with Friends, which means how much time was spent "With Friends" on Wifi.