Is there a certain way that languages are supposed to be learnt to maximize brain workout? In other words, does one way of learning a new language benefit more than the other?
I use Duolingo for learning new language(s).
I use Duolingo for learning new language(s).
http://en.m.wikipedia.org/wiki/Spaced_repetition
I believe Duolingo uses this technique to some extent.
By the way, I've been dabbling with iOS language learning apps. I've been trying to add simple games to help with the repetition that's required to learn a new language. Plus, I recently add a thousand images so people can learn by associating the foreign word with a picture. I think it can be better than associating the word with your native language. I've built apps for several languages (French, German, Italian,Russian,...). Here's my Spanish app: https://itunes.apple.com/us/app/h4-spanish-lite/id388918463?...
I also started building a language site to gather my notes in one place and try out new ideas: http://thespanishsite.com
I'll throw out a recommendation for Memrise (http://memrise.com) as well.
I made good progress with a webapp called VocLab (http://www.voclab.com/). Once you studied for a while you can track your learning progress with some detailed statistics and then tweak your forgetting curve to make sure the words are presented at the right time.