Abacus Lesson is an Android app developed by Hirokuma.App that aims to teach users how to use an abacus and improve their mental arithmetic skills. The app features all the lessons from the highly acclaimed Abacus Lesson series, which have received positive feedback worldwide. These lessons have been reworked to provide a more polite and easy-to-understand learning experience.

In addition to traditional abacus training, the app offers unique training methods that focus on finger movements and mental arithmetic. These methods are designed to enhance the efficiency of learning abacus. The app allows users to choose between vertical or horizontal screen orientations and provides the flexibility to freely adjust the position and size of the abacus and window.

One notable feature of Abacus Lesson is its ad-free experience. Users can fully immerse themselves in the lessons without any distractions. The app also offers various sound variations, allowing users to customize the volume settings according to their preferences. Additionally, users have the freedom to choose their preferred color for the abacus.

Abacus Lesson provides a goal-oriented learning experience, with users earning trophies as they achieve their learning milestones. The app also boasts smoother operability, thanks to optimization efforts that enhance its performance.

Please note that for more information and support, users can visit the app's support web page or connect with the developer on Twitter and Instagram.