A series of scalable, simple, and low cost elastomer based bilayer systems with a rigid surface layer of polymer nanocomposite were designed and prepared. The bilayer systems exhibit different surface morphologies and strain-responsive properties by forming micro-cracks or wrinkles on the top surface. Although cracks and wrinkles are typically considered as defects and mechanical instabilities, respectively, to be avoided in most cases, proper control of the formation and evolution of micro-cracks and wrinkles can lead to many novel functionalities. With the assistance of modeling, we created a series of highly sensitive and reversible mechanochromisms. Upon uniaxially stretching and releasing, as well as additional stimuli if needed, the devices can reversibly switch the topography between flattening surface and rough morphology with longitudinal micro-cracks or wrinkles, resulting in striking optical changes, including changes in transparency, luminescence, and coloration, promising for widespread application.