  Virtual Reality (VR) technology has become increasingly popular in recent
years as a key enabler of the Metaverse. VR applications have unique
characteristics, including the revolutionized human-computer interaction
mechanisms, that distinguish them from traditional software. Hence, user
expectations for the software quality of VR applications diverge from those for
traditional software. Investigating these quality expectations is crucial for
the effective development and maintenance of VR applications, which remains an
under-explored area in prior research.
  To bridge the gap, we conduct the first large-scale empirical study to model
the software quality of VR applications from users' perspectives. To this end,
we analyze 1,132,056 user reviews of 14,150 VR applications across seven app
stores through a semiautomatic review mining approach. We construct a taxonomy
of 12 software quality attributes that are of major concern to VR users. Our
analysis reveals that the VR-specific quality attributes are of utmost
importance to users, which are closely related to the most unique properties of
VR applications like revolutionized interaction mechanisms and immersive
experiences. Our examination of relevant user complaints reveals the major
factors impacting user satisfaction with VR-specific quality attributes. We
identify that poor design or implementation of the movement mechanisms, control
mechanisms, multimedia systems, and physics, can significantly degrade the user
experience. Moreover, we discuss the implications of VR quality assurance for
both developers and researchers to shed light on future work. For instance, we
suggest developers implement sufficient accessibility and comfort options for
users with mobility limitations, sensory impairments, and other specific needs
to customize the interaction mechanisms. Our datasets and results will be
released to facilitate follow-up studies.
