Uxpressia - Create customer journey maps, personas & impact maps online
Dia - Dia is a GTK+ based diagram creation program for GNU/Linux, MacOS X, Unix, and Windows, and is released under the GPL license.
Smaply - Online tool for customer journey maps, personas and stakeholder maps. Try for free. Best hub for customer experience insights. Great customer support.
draw.io - Online diagramming application
Custellence - Custellence is the most easy to use Customer Journey Mapping Tool built for customer journey managers and CX workers. The tool saves time and gives you confidence by having an intuitive interface and the right amount of journey mapping smartness
yEd - yEd is a free desktop application to quickly create, import, edit, and automatically arrange diagrams. It runs on Windows, Mac OS X, and Unix/Linux.