Is it permissible to read things other than the Qur’an, such as newspapers or any other book, in the mosque?

There is no objection to reading various types of books in the mosque, as long as they do not contain anything forbidden, such as sciences of magic and sorcery, out of respect for the sanctity of the mosque. This includes reading newspapers, but one must be careful with newspapers and magazines that contain forbidden images, such as pictures of women with exposed 'awrah (intimate parts), as well as newspapers and magazines that advocate corruption.