Fortress of the Muslim Hisnul is an Android application developed by ImanApps that is an excellent resource for all Muslims around the world. The app is based on the book "Fortress of the Muslim" authored by Said Bin Ali Bin Vahf Al-Qahtani and includes 49 additional Dua from the Quran. The app is free of cost and falls under the Education & Reference category in the Google Play Store.

The app has a user-friendly interface and allows users to listen to the Dua, add them to favorites, share, and even change the font type, size, and color. The search feature is also available to find specific Dua or chapters with ease. The app also has a night mode feature that is easier on the eyes during low light conditions. The audio files of Dua are streamed via the internet, but the app provides an option to download them as well. Additionally, users can set reminders for specific Dua at a particular time. The app is free of ads, making it a smooth and uninterrupted experience.