Prayers, Bible, Novus Ordo Calendar, Traditional Calendar; these Catechisms: Baltimore Catechisms #1-3 (original public domain), Cat. of Christian Doctrine, Roman Catechism; Cat. of St. Thomas Aq.; Haydock's Biblical Comm, and and the Catena Aurea (St. Thomas Aq. compilation of the commentaries of the Gospels by the Fathers of the Church).
NOTE: If Novus Ordo calendar crashes on update, please "Clear Data" by:
Settings (the app) > Apps > iPieta > Clear Data. (Thanks and sorry about the problem.)
iPieta links to the other modules which are optional and free.
Better app installation