Microsphere-assisted microscopy is a new imaging technique which allows the diffraction limit to be overcome using transparent microspheres. It makes it possible to reach a resolution of up to 100 nm in air while being label-free and full-field. An overview of the imaging technique is presented showing the influence of the photonic jet on the image nature and the unconventional behaviour of the magnification factor. Moreover, interferometry through microspheres is demonstrated for the 3D reconstruction of nanoelements.