There is actually a new app, just out of beta testing, called Fluent Forever that uses strategically spaced repetition like anki, but flashcard creation is way faster, plus there's audio built in. The problem with Duolingo, Babel, etc. is that they are forcing you to use English in your study of the foreign language. It's much closer to immersion to link pictures to the written and audio vocab you are trying to learn. This obviously gets trickier the less concrete your words are as you advance, but for way more info on this topic https://blog.fluent-forever.com/what-makes-fluent-forever-di... or, better yet, read the book Fluent Forever. The fluent forever method is to learn the sound needed (phonemes), then basic vocab (600-1000 words), then start building sentences to get at the trickier material.