Longoi Dot Ulun Kristian is an Android-based application designed by HukuTON for the Sabah Protestant Church. The application is a comprehensive hymn book that includes psalms, liturgy, a few bible verses, and prayers in the Rungus language. The application follows the Longoi Dot Ulun Kristian book and is an excellent resource for those who want to learn about the Sabah Protestant Church.

The application has several features that make it user-friendly. It is searchable, making it easy to find the desired hymn or prayer. The pinch zoom text feature allows users to adjust the text size to their preference. The music notation playback feature enables users to listen to the hymns and psalms, making it easier to learn and sing along. Users can mark their favorite hymns and prayers for quick access. It is worth noting that the application is open source, making it available to everyone for free.