Hey. One of the most popular language learning apps is the Babbel mobile app, and for good reason. This application is affordable, easy to use, and quite effective. They have a great support team and you can always contact babbel to resolve any issues you may have. I've been using Babbel for a few months now to learn German and I'm very happy with it. Lessons are short and to the point, and I find myself retaining most of the vocabulary and grammar I learn.