Potentially very useful. Several groups have been playing with ideas ranging from simple adapters to the optics of a smartphone camera to very novel optics. The notion of a mobile computer with net that can send images from arbitrary detectors is very compelling. I think there is going to be a lot of innovation in this area.
An example from a year and a half ago in PLoS one
1 Center for Biophotonics Science and Technology, University of California Davis, Sacramento, California, United States of America, 2 California Lutheran University, Thousand Oaks, California, United States of America, 3 California State University Sacramento, Sacramento, California, United States of America, 4 Department of Pathology and Laboratory Medicine, University of California Davis, Sacramento, California, United States of America, 5 Department of Neurological Surgery, University of California Davis, Sacramento, California, United States of America
In this paper we report the development of two attachments to a commercial cell phone that transform the phone's integrated lens and image sensor into a 350× microscope and visible-light spectrometer. The microscope is capable of transmission and polarized microscopy modes and is shown to have 1.5 micron resolution and a usable field-of-view of 150×150 with no image processing, and approximately 350×350 when post-processing is applied. The spectrometer has a 300 nm bandwidth with a limiting spectral resolution of close to 5 nm. We show applications of the devices to medically relevant problems. In the case of the microscope, we image both stained and unstained blood-smears showing the ability to acquire images of similar quality to commercial microscope platforms, thus allowing diagnosis of clinical pathologies. With the spectrometer we demonstrate acquisition of a white-light transmission spectrum through diffuse tissue as well as the acquisition of a fluorescence spectrum. We also envision the devices to have immediate relevance in the educational field.