Will Wi-Fi replace cellular technology?

As both cellular and WiFi technologies improve, more mobile traffic is carried over them. For cellular carriers, WiFi complements their network service by offloading ever increasing mobile traffic. However, at the same time, there is a danger of WiFi to compete with cellular services by interrupting its business model, as it can be a cheaper alternative to mobile Internet service. In this paper, we use a mathematical model to study the condition under which WiFi can be a threat. We also discuss important factors that can affect the competition between the WiFi and cellular technologies.