I like the lessons and the fact that native speaker correct my written, as well as my spoken exercises.
In my case, busuu.com is a great resource to learners in languages.
I have made some good friends with other busuu users while learning languages.
The voice recording exercises (Premium Function) are great to work on my pronunciation, especially if I a bit shy about talking in the language learning. I can record your voice and then send it to native speakers from the community who give you tips on your pronunciation.