Typically, nanowires are oriented laterally on a flexible substrate, with the bending applied perpendicular to the direction of the wire [21,51,58]. Uniquely, Zhang et al. makes use of arrays of vertical ZnO nanowires, perpendicular to the substrate, improving device resilience and achieving a gauge factor higher than previously reported for a single nanowire [21,50]. While lateral nanowires technically experience a bending load, it is often reasonable to assume that the nanowires are experiencing pure compression or tension, due to the geometry and mechanical properties of the device and substrate [58]. This results in a potential distribution along the c-direction of the nanowire, as opposed to across the diameter of the nanowire as in the case of lateral deflection.