[tazjin]

Personally I like Babbel. It looks a bit dated (or did the last time I used it), but its content is really good and it helped me bootstrap 3 out of the 5 languages I speak fluently.

There's no gamification like in Duolingo, you have to bring your own motivation and endure the UI, but it really does get you to the level where you can continue on your own.

[bluebarbet]

This. Same experience. It's worth noting that Babbel is designed with much input from actual language teachers, not just statisticians and coders. It also received funding from the EU, which makes a subscription a particularly good deal.