Learn Russian on Coursera
Coursera has partnerships with leading universities to offer online classes on dozens of languages. Whether you're a beginner or an experienced speaker, there's a course for you. And because Coursera is always updating its curriculum, you can be sure to find the most up-to-date information and instruction. For example, if you want to learn Korean, they have classes from the esteemed Yonsei University in Seoul.
Why go for gamified silly apps when you can get certified, world-class courses that have been developed over decades. Plus, instead of studying a language randomly, you can get a degree in the language that you can use later for work or for university.
Price: depends
Devices: Android, iPad, iPhone, and Web