It's not the worst app, neither is it good. There are languages it can teach you well. Then it has languages that it's terrible for others. Arabic is a great example. I was doing Alphabet 3 and it was teaching countries. However, it was very bad. There was this word Riga they spelled ريجا and pronounced ج which makes a J sound with a G sound. This is wrong. The closest letter you get to a G sound is غ, which doesn't make a G sound. Really bad Duo 👎