Looking at all of my total times, it's funny to see how much time has added up over the years on things I just check whenever I'm on my 3DS. Like apparently I've spent 42 hours in the Friends List! And times played is 2,304 for it.
1. Animal Crossing: New Leaf (647 hrs and 33 mins)
2. Pok?mon Y (282 hrs and 39 mins)
3. Pok?mon Omega Ruby (82 hrs and 23 mins)
I've also played a bunch of Fire Emblem Fates/Awakening and Pok?mon Sun and Yellow (17 hrs on Yellow and I haven't even finished playing it on my 3DS yet!)
On my old 3DS it's:
Animal Crossing New Leaf (2515.45 hours, which is spread over like 4 years & 3 copies of the game)
Tomodachi Life (278.39 hours)
Super Smash Bros (111.52 hours)
On my New 3DS it's :
Xenoblade Chronicles (422.20 hours)
Fire Emblem Awakening (201.30 hours)
Fire Emblem Fates (197.26 hours)