LogicLike - Improve logical thinking through engaging brain games
Swift Playgrounds - Learn serious code on your iPad in a seriously fun way
Dualnback.works - Dual N-back is a specific brain training exercise, that's been shown by research - it might improve fluid intelligence.
CodeGuppy - JavaScript coding site for kids, teens and creative adults!
JobFlare - Brain games for job seekers
PictoBlox - Coding for kids: Program robots. Make games. Do much more.