System and techniques for user input via elastic deformation of a material are described herein. The morphology of an elastic material may be observed with a sensor. The observations may include a first and a second morphological sample of the elastic material. The first and second morphological samples may be compared against each other to ascertain a variance. The variance may be filtered to produce an output. The output may be translated into a user input parameter. A device action corresponding to the user input parameter may be invoked.