On my iPhone 6S (with whichever version of iOS 11 and the Quizlet app was current in December), I used to be able to create a test and select "instant feedback". That option is gone on the iPhone X, and you can no longer change your answer before going to the next one. In addition, the app keeps logging me out, which never happened on the 6S. I contacted Quizlet, but never got a response. Any advice?