A VPK (Vita PacKage) is the standard archive and installation format for hacked PS Vita systems. Technically, it is a renamed ZIP archive containing the directory structure of a Vita application or game.
While convenient, the VPK format has notable drawbacks: psvita vpk
Understanding VPK Files on the PS Vita: Structure, Usage, and Limitations A VPK (Vita PacKage) is the standard archive