This paper argues for explicit consideration of datafidelity during development of context-aware systems. Increasingthe amount of data captured, stored, and distributed does notalways translate into into increased fidelity, and we can leveragethis to avoid unnecessary energy overhead and increase devicebattery life. We introduce Context-Awareness Fidelity Expression(CAFE) as a framework for deliberately specifying applicationdata fidelity adaptation with the aim of using context-awarenessto reduce energy consumption.