Từ điển Ngữ Pháp Tiếng Nhật is an Android-based application developed by Nahu Studio that provides a comprehensive Japanese grammar dictionary for Vietnamese learners. The app offers over 600 grammar patterns, ranging from basic to advanced levels, with Vietnamese translations and examples. Users can search for specific grammar patterns and their meanings, study grammar by JLPT levels, practice with exercises, and track their progress. The app also allows users to bookmark important grammar patterns and mark the ones they have learned. Additionally, users can listen to the audio of the example sentences in Japanese.

However, it's important to note that the app's GUI is only available in Vietnamese.