So far we've only seen third-party download game in the Nintendo 3DS eShop, the decent but could-do-better Let's Golf! 3D. That offering is set to multiply significantly by year's end though, as Nintendo announces the 3DS download games on the way before 2012.
Monster Hunter Generations! Disney Art Academy! Tumblestone! Much more!
Tokyo Mirage Sessions! Mario & Sonic! Mighty No. 9! Nintendo Selects! More!
Donkey Kong Country 3! Kick and Fennick! Fire Emblem DLC! More!
Splatoon discount! Professor Layton Movie! TAP TAP ARCADE 2! More!
Secret Files Tunguska! 3 Street Fighter Games! 3 TurboGrafx-16 games! More!
LEGO Star Wars! BoxBoxBoy! Battle Cats! Zero Time Dilemma! DLC! More!
Lots of Kirby! Fire Emblem Fates Revelation! Terraria on Wii U! Much more!
Buddy & Me! A Shadow's Tale! Wind-up Knight 2! Demos! FE DLC! More!
One hundred discounted games, no word on Western equivalent yet
You'll have to wait until October, though