Hocdan - Đơn giản thôi mà is a free Android app developed by Tran Chi Hieu, designed for those who want to learn to play guitar and ukulele without prior knowledge. The app is based on a learning community of over 300,000 members, with 30 instructors who are constantly working to improve the app. The app's goal is to make it easy for anyone to learn to play guitar and ukulele, regardless of talent or time constraints.

The app offers a wide range of features, including access to guitar and ukulele lessons, a database of popular Vietnamese songs with chord charts, a selection of experienced instructors, personalized learning paths, and the ability to save favorite lessons and tutorials. Additionally, users can showcase their skills on the app's performance platform, and enjoy other useful and engaging features that make learning guitar and ukulele fun and easy. With nearly 1,000 lessons already available and new content added daily, Hocdan - Đơn giản thôi mà is the perfect app for anyone looking to master the guitar or ukulele.