How often should I review my notes?
There are several algorithms for scheduled repetition of information on flash cards. It's possible that the software you liked uses one of these. This Wikipedia article on spaced repetiton discusses Pimsleur's graduated-interval recall and Leitner system, among others. This isn't the easiest topic to search for, but the Wikipedia article calls it "spaced repetition", and includes a list of alternative names. That should help you do further research.