I have both of these games and I prefer Brain Age/Training because it's really fun, and has loads of training modes like 20x calculations, 100x, Head Count, Low to High etc.. It keeps you busy for a while when you've got nothing else to do. BB Academy is more of a puzzle type game where you take tests on Analyse, Think and stuff lol. But overall they are both good games, but Brain Age is the best in my opinion because it has alot more modes and things to do including unlockables!
....I've covered that up! xD