This application behind the entire book of spiritual doctrine base, without the need to have internet for reading.

The Big Book of Spirits, by Allan Kardec.

Spiritual philosophy

Containing the principles of spiritist doctrine of the immortality of the soul, the nature of spirits and their relations with men, the moral laws, the present life, future life and the future of humanity - according to the teaching of the higher spirits, through various mediums, received and ordered by Allan Kardec.