Analysis
Analyse Curvature
Curves
To display the curvature of a curve at every evaluated point, enable curvature combs in the mesher modifier.
Surfaces
For surfaces, there is a specific modifier: SP - Curvature Analysis. It can be added automatically to every surfaces through N Panel > SurfacePsycho > View > Curvature Analysis. By default it displays the mean curvature
Matcaps
To register the matcaps shiped with the addon, go to Edit > Preferences > Add-ons > SurfacePsycho > Psycho Matcaps and click Add. They will appear in the matcap list. For better analysis, increase surfaces resolutions, enable Exact Normals and EEVEE's high quality normals (More info here).