雑学常識問題9000問 is a free Android app developed by Mejiro Publications that offers a vast collection of more than 9000 questions spanning across 62 categories. It is the largest collection of general knowledge and trivia questions available on any app. The app is designed to improve your knowledge, communication skills, and help you create interesting conversation topics in social gatherings. It is also an excellent resource for those preparing for interviews or general knowledge-based exams.

The app offers two modes: "Normal mode" and "Quiz mode." In Normal mode, you get a list of questions and answers categorized by topic, with no explanations or additional features. It is perfect for those who want to use the app as a reference book. In Quiz mode, you get a question, and you need to answer it before checking the answer. After answering, you can click on the "Correct" or "Incorrect" button, which will take you to the next question. The app keeps track of your correct answers and presents your score at the end.

Overall, 雑学常識問題9000問 is a great app for anyone looking to expand their general knowledge and trivia skills.