Proxyman.io - Proxyman is a high-performance macOS app, which enables developers to view HTTP/HTTPS requests from apps and domains.
JunoRestClient - JunoRestClient helps you to create, organize and test your REST API quickly.
Endpoints - View and respond to requests on an HTTP endpoint
Amazon API Gateway - Create, publish, maintain, monitor, and secure APIs at any scale
HTTP Toolkit - Beautiful, cross-platform & open-source tools to debug, test & build with HTTP(S). One-click setup for browsers, servers, Android, CLI tools, scripts and more.
Assertible - Assertible software provides you with a simple and quick way to monitor your web services. It comes with automated QA tools that users can utilize to test and monitor their web services on different platforms and environments.