Was interested in Japanese. The app leads you through some basic familiarization phonetically, but also prompts you write in Japanese with absolutely no crash course on how to navigate the Japanese keyboard. I've tried playing dumb and getting those questions wrong, but you're locked until you get it right. How can you get it right if you can't navigate the keyboard? Even worse, the app stuck my keyboard in Japanese for all phone functions. Fixed by restarting phone. Just... yikes.