Brain Age: Concentration Training for Nintendo 3DS Reviews by Gamers

There are several minigames to unlock but you can get all of the devilish training ones in about a week or so. To unlock every unlockable you'd have to play it for more than a month. I played it for a couple of weeks and unlocked klondike, spider, and peg solitaire and several interesting strategy/puzzle games. You get credit for just playing one game a day but you can play the solitaire as many times as you want until you win a hand. I love that you go up or down in levels within a game depending on how well you do each round so it doesn't get too frustrating.