Insomnia

If you have ever worked with HTTP APIs, then you probably know how difficult and time-consuming building new commands for every test case, changing API keys and working with scripts really is.
Insomnia is a hi-tech and comprehensive piece of software that provides you with all the necessary tools and a suitable environment for testing, organizing, running and debugging HTTP requests and APIs.

Cross-platform utility that can be installed with the minimum amount of hassle

First thing's first, since it is cross-platform, Insomnia can be run just as smoothly and efficiently on the most popular operating systems out there, namely Windows, macOS and Linux.
The application can be quickly deployed on your computer thanks to its streamlined, generic installer that does not require much intervention from your part in order to get the job done.

One of the main reasons for using Insomnia is its modern interface

Upon first launching the app, you are greeted by a black-themed, very well organized user interface that looks right at home on modern iterations of Windows. The first thing that might become evident is how well you can organize your work with the help of Insomnia.
This said, on the left side of its main window, you can create workspaces and folders, manage environments, add requests and easily import and export data. Once you have created requests, you can specify URL, payloads, headers and get detailed information about their behavior.

Specialized set of features that make the whole process of testing APIs more enjoyable

Thanks to its configurable timeout, support for query parameters and nunjucks templating, you can get very accurate details about the responses, as well as view the code, body, headers and cookies statuses.
Since this app is all about boosting your productivity while testing APIs and requests, you should know that you can also define API key variables globally and instantly switch between environments and sub-environments with no more than a few mouse clicks.
Viewing and managing cookie-based APIs is also something that Insomnia can help you with, as well as generate boilerplate code snippets for multiple language libraries, such as Java, Python, Swift, Go, NodeJS, just to name a few.

Test, run, organize and debug HTTP APIs with the help of this efficient app

Taking everything into consideration, with the help of its very well-structured interface and its set of specialized features, Insomnia is a tool that will surely come in handy whenever you have to deal with HTTP APIs by improving your workflow.