The app does not contain any viruses, does not collect any personal information. It is 100% free too. There are some ads running in it, every time you click on them, you support the app developers.
The Practice of the Presence of God is a book of collected teachings of Brother Lawrence (born Nicholas Herman), a 17th-century Carmelite monk. Compiled by Father Joseph de Beaufort. The compilation includes letters, as well as records of his conversations kept by Brother Lawrence's interlocutors. The basic theme of the book is the development of an awareness of the presence of God.
The text attempts to explain Lawrence's method of acquiring the presence of God. A summary of his approach can be gleaned from the following passages. "That he had always been governed by love, without selfish views; and that having resolved to make the love of God the end of all his actions, he had found reasons to be well satisfied with his method. That he was pleased when he could take up a straw from the ground for the love of God, seeking Him only, and nothing else, not even His gifts." "That in order to form a habit of conversing with God continually, and referring all we do to Him; we must at first apply to Him with some diligence: but that after a little care we should find His love inwardly excite us to it without any difficulty."