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.
Corecon - Corecon offers integrated estimating, project management, and job costing for small to medium-sized construction companies.
draw.io - Online diagramming application
CoConstruct - CoConstruct's project management software helps custom builders & remodelers coordinate projects, communicate with clients & crew, and control.
PlantUML - PlantUML is an open-source tool that uses simple textual descriptions to draw UML diagrams.
Procore - Procore is the world's most widely used construction project management software. Easy to use, mobile platform with unlimited user licenses.