What is the ruling on entering a mosque with a mobile phone that contains pornographic video clips?

It is not permissible to look at or keep indecent pictures on the phone; rather, they must be deleted. A phone containing such pictures should not be brought into the mosque, out of reverence for the sacred ordinances of Allah Almighty, as He says: "That [is so]. And whoever honors the sacred ordinances of Allah - it is best for him in the sight of his Lord." One who does this should be advised with wisdom and gentleness.