Top 20 NuGet ReST Packages

This is the Flurl.Http package, repackaged with strongly named assemblies. See https://flurl.io/ for the official project.
Twilio REST API helper library
Simple.OData.Client is a multiplatform OData client library supporting .NET 4.x, .NET Standard, .NET Core, iOS and Android. The adapter provides a great alternative to WCF Data Services client. It does not require generation of context or entity classes and fits RESTful nature of OData services. ...
A fluent, portable, testable HTTP client library.
Simple.OData.V4.Client is a multiplatform OData client library supporting .NET 4.x, .NET Standard, .NET Core, iOS and Android. The adapter provides a great alternative to WCF Data Services client. It does not require generation of context or entity classes and fits RESTful nature of OData services. ...
This is the core support library for HL7's FHIR standard (http://hl7.org/fhir). It contains the core functionality to working with RESTful FHIR servers: POCO classes for FHIR, parsing/serialization of FHIR data and a FhirClient for easy access to FHIR servers.
A .NET SDK to make voice calls & send SMS using Plivo and to generate Plivo XML
.NET Standard 2.0 version of ServiceStack
Twilio helpers for ASP.NET MVC versions 3 through 5.
ServiceStack is a simple and fast alternative to WCF, MVC and Web API in one cohesive framework for all your services and web apps that's intuitive and Easy to use! To get started see: https://servicestack.net/getting-started
Easy-to-use typesafe REST API client library, which is simple and customisable.
Azure Key Vault enables users to store and use cryptographic keys within the Microsoft Azure environment. Azure Key Vault supports multiple key types and algorithms and enables the use of Hardware Security Modules (HSM) for high value customer keys. In addition, Azure Key Vault allows users to secur...
The DocuSign NuGet Package makes integrating DocuSign into your apps and websites a super fast and painless process.The library is open sourced on GitHub, look for the docusign-csharp-client repository. Join the eSign revolution!
Lightweight and implementation-free interfaces for DTO's, providers and adapters.
Provides common error handling, tracing, and HTTP/REST-based pipeline manipulation.
This is a portable class library which makes it easy to access the Bing Maps REST services from .NET.
Chilkat .NET Class Library (64-bit) for SSH/SFTP, FTP, POP3, SMTP, IMAP, SSL/TLS, Zip, REST, OAuth2, HTTP, RSA, XML DSig, Encryption, Compression, XML, Socket, XMP, HTML to XML, JSON, JWT, OAuth1, conversion, PKCS12/PFX, Java Keystore, ASN.1, PEM, ECC, Async, ...
Restores Newtonsoft.JSON as the default serializer for RestSharp.
Lightweight and implementation-free interfaces for DTO's, providers and adapters.
Tweetinvi is an intuitive .NET C# library to access the Twitter REST API. It is a .NET Core library that can be used for development on Windows, Windows RT, Windows Phone, Xamarin Android and Xamarin iOS. Tweetinvi is also compatible with Windows 10 Universal Apps.