I have tried a few language learning apps and this one seems really great so far. The lessons give you the information you need while also being fast paced and interesting (for learning a language).
I have used the French beginners Lessing one and two and I am currently halfway through 3. I havent found any bugs my only complain is the voice recognition seems to be very testy. If I am not in a completely silent room it has difficulty picking up what I say. Even after adjusting the mic settings several times.
Considering you can pay several hundred dollars, for similar products I think babbel is a very good value for money
Nlmabf about Babbel – Learn French, v4.4.5