Overall, the above-mentioned theoretical models have contributed to our understanding of user acceptance factors and behavior.However, there is still a need for further studies in m-payment users’ behavior. While UTAUT is a good candidate for our study,we believe that the extension of TAM serves our research purposes better than UTAUT. The constructs used in our model (i.e., individual differences and system characteristics) are more specific than
the generalized constructs used in UTAUT. We posit that systems characteristics and individual differences affect users’ perception of m-payment. To investigate individual differences in detail, two factors, personal innovativeness and m-payment knowledge, were identified. Along with these two factors related to individual differences,
we also identified four system characteristics (mobility,reachability, compatibility, and convenience). Below we discuss
in detail each category with its constructs.