Today＊s smartphone handsets offer a wide range of functions (phone, GPS, Bluetooth, WiFi, .) to customers, although are still perceived as expensive and energy consuming (requiring a daily recharge). The aim of this talk is to show how microwave measurements impact smartphone design. By optimally engineering the type of measurements made before and after design (linear, nonlinear, loadpull, modulation, .), the efficiency of the design process not only increases, but tougher specifications such as smaller form factor and lower energy consumption can be met more easily. This observation is especially valid in the design of green multi-mode wireless radios, due to the delicate balance between energy efficiency and linearity (that is, cross talk between channels).