Intermediate Japanese: Nothing to see here
I was looking forward to this course and as I don't have iOS device, I've had to wait for the Android app which was released today. I would describe myself as an intermediate Japanese speaker and I think it's a fair assessment.
It was disappointing. I tested through the course in probably less than an hour. I don't like the way it pronounces は when it's a particle. It is pronounced "ha" when it should be pronounced "wa".
I don't know what it's like for beginners as I didn't do the early stages but maybe it's OK. I guess it's back to iKnow for me for Japanese.
But I'll continue doing the Spanish, here. It's a lot of fun.
It is a beta so the pronunciations could be fixed, and Duolingo did say the course will help you pass JLPT N5, so it's clear the course is for beginners and won't take you that far.
If you successfully finished JLPT N2, than any Duolingo Japanese course may not help you to improve your knowledge. I have only JLPT 3 (when there were 4 Level) and Kanken 8 (7,6,5? I´ve forgotten...) and I rushed through the Duolingo Japanese course within a few hours (about 3/4 of the tree I finished by the initial placement test, the rest by test out option). If you have JLPT N2, your Japanese knowledge is much more than mine.
But if they solved the actual issues, which are mentioned in many posts here (also some of mine), and there are enough interested persons, the course will surely be improved after a while, but for N2 or N1 graduates, it may stay too easy, I think.
Duolingo has to address the first beginners and a advantage of this course is, that they do not use romanized Japanese and teach the Japanese characters from the beginning. So the Duolingo students have a hard time to recognize these about 100 Japanese kanas and especially the few kanji and kanji compounds, Duolingo uses. So this level of difficulty is good enough, I think. I do not expect to learn more Japanese with Duolingo, but I would like to support the incubators by reporting issues and additional answer options.
I would suggest, you should use real life sources to improve your Japanese, you are good enough for that and - if you want - support the Duolingo incubators as me, because your knowledge would be surely very appreciated!
I'm a beginner who just recently started learning kana, so the Duolingo Japanese course is just about right for me. It's helped me remember the difference between similar hiragana such as sa and chi. I'm learning some new vocabulary and learning how to spell words that I already recognize aurally.
Have you tried the reverse course - English for Japanese speakers? I'm intermediate-ish in Spanish and French. The reverse tree was more interesting and challenging for me in those languages as you have to answer in the language you are learning. Answering in English is relatively easy for English speakers.
Yesterday I tried out this course on the Android app too. I agree that it's too easy on the app for people who've already learnt a bit of Japanese.
However, I think you might appreciate this course when it eventually comes to web browser. On this account I've been doing it solely on web browser for over a month. I've found the web version reasonably good for low-intermediate Japanese sentence practice.
Since I always have the audio switched off on Duolingo as I'm listening to music anyway, I'm therefore not affected by the pronunciations being incorrect. :P
So have a go again when the web version of this course comes out ("should be available on Web at some point this year"...)
In the meantime, the English from Japanese course as a reverse tree works really well. It is a little too easy again on the app, but on the web browser it seems pretty decent for intermediate level. Just make sure to turn off the speaking and listening exercises if you try it as those don't involve any Japanese... I've been using the reverse tree on web for a long time on my other account. ^^
i did not like memrise at first, but the regular updates to their official courses kinda won me over. when they first added japanese they only used hiragana, i tried but it hurt my eyes and my brain, i couldn't do it. now they have two sets of courses, one that uses kana and kanji, and a romaji one for those who are intimidated by the script. both sets have the cute meet the natives video that i find quite useful in getting used to the natural flow of spoken japanese. by no means perfect but definitely a huge improvement in a short amount of time.