ASTAR is a TEM attachment that couples beam scanning with electron precession in order to provide orientation and phase mapping of TEM specimens. The process consists in (i) acquiring the precessed electron diffraction (PED) patterns at every location of the scanned area and (ii) analysing the patterns with a dedicated template matching technique. On FEG (respectively LaB6) equipped transmission electron microscope, orientation and phase maps are reconstructed with a spatial resolution of 1 nm  (resp. 10nm) for regions of interest of up to 100 µm2 (resp. 300µm2[E1] ). The present work will describe the method and illustrate the potential of the technique in various fields of research with results concerning metallurgy, microelectronics, geology but also biology and pharmacy. As PED patterns are systematically stored during the acquisition, numerous post processing strategies may be considered to complement the material characterization. The most promising developments will be introduced. In particular the huge potential of virtual bright- and dark-field images reconstruction will be discussed. Also, the recent correlation coefficient map construction technique that highlights the inner grain or phase boundaries will be described.