Prayer Book is an Android application developed by Igor Apps that offers a vast collection of prayers and commandments. This full version app contains hundreds of prayers for various purposes and occasions, including daily devotional, protection, healing, and financial prosperity. The app also includes prayers from different categories like Roman Catholic, St. Jude, Hail Mary, Peace Prayer of St. Francis, and many more.

Moreover, the app provides the Ten Commandments, which are a set of biblical principles that play a fundamental role in Christianity and Judaism. These principles include worshipping only God, honouring one's parents, and keeping the Sabbath, among others. Additionally, the app offers a King James Bible and well-known prayers such as "Our Father, Our God", "God is Great, God is Good", Giving Thanks, My Children, The Angelus, and many others. Overall, Prayer Book is a comprehensive collection of prayers and commandments that caters to different needs and occasions.