I strongly recommend [Language Transfer ](https://language transfer.org). The best language course I have ever done, and I have done many (I speak five languages, at varying levels of fluency).

They have an app, that is simple, streamlined, and very functional.

The app also has also an Introduction to Music Theory course which people say is very, very good.

I've been using LingoDeer for the past few days since hearing this news, and so far it's not too bad. The social features are severely lacking compared to Duolingo (my friend group goes hard on the friends quests lol) but they have a lot more grammar explanation and whatnot available that duolingo doesn't. Plus, LingoDeer seems much less focused on learning for tourism, and more for actual learning.

Note this is all for the Japanese course, no idea how their other courses are.

Also interested in this