Sonic is a platform that integrates remote control debugging and automated testing of mobile devices, and strives to create a better user experience for global developers and test engineers.

Mock and modify HTTP request for exploratory testing.

Charles is a HTTP proxy that enables you to see traffic between your machine and the backend

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.

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

Jest is a delightful JavaScript Testing Framework with a focus on simplicity.