Mental Math Trainer is a free iPhone application developed by ARTEM KAZANOVICH. Designed for all ages, this app helps users improve their mental calculation abilities in addition, subtraction, multiplication, and division. With just 5 minutes of practice a day, users can see progress in as little as one week.

One of the standout features of Mental Math Trainer is its high user rating, averaging over 4.5 stars. This makes it one of the most downloaded math apps available. Additionally, the app does not contain any ads or in-app fees, providing a seamless and distraction-free learning experience.

The app is suitable for students at various levels of education, from elementary school math to high school and college-level math. It covers a wide range of topics, including basic arithmetic, algebra, geometry, pre-calculus, calculus, and statistics. The app also offers flexible settings and detailed statistics of users' results, allowing for personalized learning and progress tracking.

Overall, Mental Math Trainer is a comprehensive and user-friendly app that offers a convenient way to enhance mental calculation skills. Whether you're a student preparing for exams or an adult looking to improve your math abilities, this app is a valuable tool for anyone seeking to sharpen their calculation skills.