Quran By Subject is an Android application that categorizes the Arabic ayas or verses of the Holy Quran by subject. It has more than one hundred subjects, including all the stories of the prophets in the Quran, as well as very useful subjects such as Creation of man and universe, Satan, Prayers or Duaa, Nature of man, Description of heaven and hell, Laws of Islam, Angels, and God's names and attributes he describes himself with. This app is open source, and you can also run it on your own server for free.

The app is easy to use and navigate, and its categorization system is helpful for anyone who wants to study or research a particular subject in the Quran. With this app, users can quickly find the relevant verses on a particular topic, making it a useful tool for students, scholars, and anyone interested in studying the Quran in-depth. Overall, Quran By Subject is a valuable addition to any Quranic library, and its open-source nature makes it accessible to all for free.