I find IPE to be a life-savior when it comes to generating physics illustrations which come with their share of math toppings. The editor has nice utilities for latching on to the boundaries, intersection, center etc of geometric figures. The spline tool is the best I have seen anywhere. Layers are handled with grace. LaTeX is rendered instantly. It is very easy to produce a multipage document. What more can one possibly want?
Sketch - Professional digital design for Mac.
Inkscape - Inkscape is a free, open source professional vector graphics editor for Windows, Mac OS X and Linux.
LaTeXDraw - LaTeXDraw is a graphical drawing editor for LaTeX.
Adobe Photoshop - Adobe Photoshop is a webtop application for editing images and photos online.
draw.io - Online diagramming application
Affinity Designer - Professional creative software, exclusively for Mac.