MOPEX (MOsaicker and Point source EXtractor) is a package for reducing and analyzing imaging data, as well as MIPS SED data. MOPEX includes the point source extraction package, APEX.
MOPEX is designed to allow the user to:

• perform sophisticated background matching of individual data frames
• mosaic the individual frames downloaded from the Spitzer archive
• perform both temporal and spatial outlier rejection during mosaicking
• apply offline pointing refinement for MIPS data (refinement is already applied to IRAC data)
• perform source detection on the mosaics using APEX
• compute aperture photometry or PRF-fitting photometry for point sources
• perform interpolation, coaddition, and spectrum extraction of MIPS SED images.

MOPEX comes in two different interfaces (GUI and command-line), both of which come packaged together. We recommend that all new users start with the GUI, which is more user-friendly than the command-line interface