OSIRIS-APophis EXplorer (APEX) is the extended mission for OSIRIS-REx, sending the spacecraft to a new destination after the sample collected from asteroid Bennu was returned to Earth in September 2023. APEX will rendezvous with near-Earth asteroid Apophis just after it makes a close approach to Earth in 2029. Following the observation strategy performed at Bennu, APEX will use the same instrument suite to perform comprehensive observations of this potentially hazardous object. Although it cannot return a sample, the mission will also use the spacecraft thrusters to excavate the surface for further analysis. OSIRIS-APEX is led by PI Daniella DellaGiustina of the University of Arizona and managed by GSFC.