it's an okay app the only issue I have is when you need to switch your native language it does not let you, it's difficult for bilingual people. I am a Mexican-American for example so I speak English and Spanish but I prefer to have things translated in English, not Spanish and when I tried to change it it does not let me. Yes I can change it in the options of my profile, but when I go under lessons it still translate Korean to Spanish instead of English. Very frustrating!