As Internet of Things (IoT) and wearable devices become the next wave of emerging markets, it is very necessary to provide a set of sensors related to target applications so that decision-making becomes more reliable from collected data. However multi-sensor approach results in higher data rate and larger power consumption, which may not be accepted by application requirements, e.g. mobile health-care. In this paper, a sensor-fusion approach will be introduced to provide an energy-efficient and data-reliable solution. By exploiting event-driven architecture, energy efficiency can be enhanced; on the other hand, analysis accuracy can be further improved with the support of multi-data sets. As a result, both power consumption and data bandwidth can be minimized with better accuracy to meet those specifications in battery-operated devices. A test vehicle related to mobile health-care applications will also be introduced to demonstrate the feasibility of our proposal.