When concluding the prayer, to whom do we say, "Peace be upon you and the mercy of Allah"? Is it to the angels or to the worshippers?

The taslim (salutation) is a pillar of prayer, and one is not released from it except by performing it, due to the Prophet's (PBUH) saying: "Its dissolution (permissibility of exiting) is the taslim." This is the view of the majority of scholars. When performing the taslim, the worshiper intends to exit the prayer, and to greet the imam, those to his right and left, and the guardian angels. The one praying alone intends to exit the prayer and to greet the guardian angels.