If you're looking for a way to train your brain and improve your problem-solving skills, IQ Test - Brain Booster app by Nana Tech might be just what you need. This free app, available for Android, offers a comprehensive IQ test that consists of 39 questions, gradually increasing in complexity.

To complete the test, you'll need to use your observation, analysis, reasoning, and calculation skills to choose the right geometric shapes and complete larger images. The app measures your fluid intelligence (Gf), which is your ability to reason and solve problems.

The IQ Test - Brain Booster app is offline, meaning that you can take the test and get your score without internet connection. The results are provided free of charge, and the app claims that taking the test will help you boost your brain, improve your problem-solving ability, and increase your brain sensitivity.