What are some alternatives?
Adobe Illustrator - Adobe Illustrator is a vector graphics editor.
LucidChart - LucidChart is the missing link in online productivity suites. LucidChart allows users to create, collaborate on, and publish attractive flowcharts and other diagrams from a web browser.
CorelDRAW - CorelDraw is a world’s most leading Graphic Design Software solution created by Corel Corporations.
Sketch - Professional digital design for Mac.
draw.io - Online diagramming application
Inkscape - Inkscape is a free, open source professional vector graphics editor for Windows, Mac OS X and Linux.