Introduction: The progress of science at the turn of the 21st century has made it possible to create new quantum engines (QEs), powered by physical vacuum energy. The thrust force generated by QEs can be applied to the vehicle’s body directly, with no transmission required. This will completely transform the transportation industry: the traditional cars will be upgraded with QEs and thus converted into quantomobiles. Ahead of this major transition, we believe it necessary to outline the quantomobile theory. Methods: We formulate and review the key concepts of the quantomobile theory from the systemic, philosophical standpoint, drawing analogies from the existing automobile theory. We also present models of this hypothetical vehicle’s components and functions. Results: The study results in the following: a structure of the quantomobile theory; an overview of the vehicle’s hypothetical configuration, its constructive and operational features, force balance specifics, and movement patterns, along with various aspects of acceleration time, off-road performance, ease of operation, and other features; an analysis of the vehicle’s thrust and speed characteristics that are shaped by the QE thrust. The vertical component of the thrust vector is sufficient both for hovering and pressing down the vehicle. This enables both the airborne and underwater quantocraft modes, transforming the quantomobile into an all-purpose, multi-modal vehicle (multi-modal quantomobile, or MMQ). Discussion: The quantomobile theory, even on the purely hypothetical level, will be of use at the early stages of designing quantomobiles and their subclasses, conducting R&D, developing infrastructure, and supplying the transportation industry with the equipment and HR required.