I'd been using Duolingo for learning German for 1-2 months. Was it the right tool for learning new language? Not for me!
Duolingo doesn't take advantage of spaced repetition. I got sick and tired of successfully answering the same word for 15 lessons and then not seeing that word ever again. In total I did 2.5 units, so there was plenty of space for spaced repetition.
Overly gamified. When I do my first lessons of a day, there are so many "achievements" that they distract my focus and learning. Maybe the development could be focused better on the quality of learning instead of throwing tons of fake achievements?
I'm not a native English speaker. So I often ended up writing the longest sentence in English translation and have it marked as "false" just because of forgotten "the". Good job, Duo! You spot me...
The UI is also too primitive. For example, when I need to make a sentence out of multiple separate words provided in flashcards, I can't change the order of the words. I can only add the word to the end of the sentence, but not insert it. This again often results in having to rewrite the whole sentence, when the missing word is in the beginning of the sentence.
The overall feeling of the learning felt slow and boring. In the first weeks I was excited, because I was learning the new language. However, later when I was opening Duolingo, I felt more and more like it was a boring bureaucratic process that I have to go through. Why? Too many lessons of the same topic, too much repetition, too slow. I felt that throwing away 2/3 of the content would result in a 3 times better app.
So while this may be a tool for learning a new language, I consider it a really non efficient, non structured way of learning, having poor UX. I dumped Duolingo ~1 month ago changing my learning strategy. Now I feel more satisfied with my new learning process and feel that I'm improving faster.
What's Your experience learning languages? Have You used Duolingo?