In an effort to reduce healthcare costs, home healthcare devices are seeing increased use. However, many of these devices are specialized, operate independently and use proprietary interfaces, diluting the cost savings. Smartphones offer a way to retain these cost savings by serving as a sensor hub within the home. In this paper we describe an extensible framework that combines a mobile device interfacing with health sensors in the home, a set of ontologies to map sensor data to clinical information standards such as IEEE 11073, and a cloud-based reasoning and mapping system built with OWL, SPARQL and SPIN. This approach capitalizes on the ease of use and low cost of smartphones, and the computational power and flexibility of a cloud-based semantic web reasoner. A proof of concept implementation is presented.