TestRail’s web-based test case management is used by thousands of great QA and Development teams to efficiently organize, track and manage software testing.
draw.io - Online diagramming application
PractiTest - PractiTest is a cloud based Innovative test management tool.
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.
Sauce Labs - Test mobile or web apps instantly across 700+ browser/OS/device platform combinations - without infrastructure setup.
PlantUML - PlantUML is an open-source tool that uses simple textual descriptions to draw UML diagrams.
Qase - Test case management software for QA and development teams that helps you make your product better.