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

REST API client library for .NET

A diff tool for comparing PDF files

Website and mobile testing at every stage of development

Design, debug, and test APIs locally or in the cloud

RapidAPI for Mac is a full-featured HTTP client that lets you test and describe the APIs you build or consume. It has a beautiful native macOS interface to compose requests, inspect server responses, generate client code and export API definitions.