After about 2 months of lessons and activities, I feel like this is an overlooked app that you don’t hear much about. It somewhat follows the Fluent Forever ideas and offers a good mix of materials.
I had originally complained to the (very responsive) developer about some of the questions having answers that were "ambiguous", but as I am learning more, I'm realizing that even the multiple choice questions really make you think about the answer. Because of this, I'm finding the lessons "stick" better. Using Babbel as a counter example, sometimes their answer is so obvious that it could be picked without even knowing any of the language.
Lessons are short enough to easily fit in a busy day, but not so short as to be "gamified." As a beginner, the lessons so far haven’t been "hard", but they can be challenging. I’m enjoying them each day.
Everyone learns differently, so your mileage may vary, but for me - having tried all of the big names (Babbel, Busuu, Rosetta, etc) - this is definitely worth a look.