Portable sensory devices carried by humans-which are referred to as Human Probes-facilitate easy-to-use sensing and monitoring of urban areas. However, when each Human Probe individually senses and transmits information, the sensing activity is inefficient in terms of energy consumption. In this paper, we propose an Architecture of Quality-enhanced Urban Information Blending and Aggregation (Aquiba), in which the sensing activities carried out by the Human Probes are adjusted autonomously under different conditions. Aquiba involves cooperative sensing that helps in achieving high-fidelity sensing while minimizing overall energy consumption. To demonstrate the validity of cooperative sensing, we implemented a prototype device by using a commercial off-the-shelf mobile phone and conducted a field experiment. The experimental results show that Aquiba is capable of providing high-fidelity sensing and reducing energy consumption efficiently.