I agree Duolingo is not a substitute for more immersive learning or even just taking classes. It's especially not very ideal for the spoken parts of a language

I agree Duolingo is not a substitute for more immersive learning or even just taking classes. It's especially not very ideal for the spoken parts of a language since it can't do the best job at judging your pronunciation and you're not going to spend a lot of time in the app having coherent conversations in another language. From my experience so far, it's good at teaching you the basics of a language so you can be just good enough at sounding like an idiot in front of your Brazilian friend. That said, I have heard some people pairing it with HelloTalk to get that immersion piece. It's an app that lets you talk with others in the language you're trying to learn, and vice versa they too are trying to learn your language