The app offers 10 multiple-choice questions with explanations with an additional 1000 questions available as an in app purchase.
Detailed pictures are available for some questions. Explanations are linked to additional online references and can be accessed via the more button on the explanation page.
Missed questions are retained in the question pool and displayed again until you get them correct on the first attempt.
Statistics are generated and include a list of keyword topics missed. These keyword topics will enable you to determine what areas need further study.
Repeat all questions as many times as you wish.