Today's wireless networks and devices support the dynamic composition of mobile distributed systems, according to device connectivity. This has in particular led to the introduction of a number of supporting middleware. However, such solutions need to be complemented with adequate modeling and verification support towards enforcing the correctness of the dynamic mobile systems with respect to both functional and non-functional properties. Building on the elegant properties of software architecture modeling, this paper introduces base modeling of mobile software components, which integrates key features of the wireless infrastructure and allows for reasoning about the behavior of dynamically composed systems.