Burp or Burp Suite is a set of tools used for penetration testing of web applications. It is developed by a company named Portswigger who make freely available a Web Security Academy which has a range of lessons on penetration testing.

Voiden is a developer-first API client with local storage, Git-integrated, all based on markdown + offline support.

Postman is an API platform for building and using APIs. Postman simplifies each step of the API lifecycle and streamlines collaboration so you can create better APIs—faster.

ReadyAPI is a low-code API testing platform for development teams that care about creating test automation across any workflow.

Built for developers and testers alike, SoapUI is the only open source tool that covers the entire testing spectrum (functional, security, load, mocking).

Streamline your API testing, integration testing and test data management.