I found out about Duolingual from a British Council online teaching English course about MOOCs.
Luis von Ahn, founder of duolingo, talks about the development of the free language teaching MOOC and technological developments in general.
So, I have joined, and I have been trying to re-learn French (I studied it in high school for 5 years, and ended up with a qualification, and while my reading is perhaps at elementary level, speaking and listening are pretty poor).
I have been doing the exercises on my mobile phone. This is a major positive feature – although you would need a headphone in order to use in public areas.
I like how it remembers what I have done, how I have a certain number of ‘hearts’ or lives, and if I get too many questions wrong, I need to go back to the beginning of the exercise. There are a variety of exercises, from very simple matching, to translating into English, translating into French, listening and translating, and writing. If you just get one letter wrong, it might let you off, and accents and symbols particular to French are not needed (garçon and garcon both accepted). You get email remainders, or on your mobile you get a reminder on your screen. Some ‘social’ pressure to keep going.
Anything bad? I guess the social element is missing – you are not learning with others.
I wish it had a Chinese version.