STEM Helper is a mobile application that offers users the ability to take various quizzes and tests on a variety of topics such as history, science, sports, entertainment, and more. The app usually includes multiple choice questions, timed tests, and often offers a leaderboard where users can compare their scores with other players. Users can challenge themselves or compete with friends to see who can achieve the highest score. A free quiz app is an excellent way to test your knowledge, learn new things, and have fun while doing it.