- Supports .NET 3.5+, Silverlight 4, Windows Phone 8, Mono, MonoTouch, Mono for Android
- Easy installation using NuGet for most .NET flavors
- Supports strong naming using NuGe for most .NET flavors
- Automatic XML and JSON deserialization
- Supports custom serialization and deserialization via ISerializer and IDeserializer
- Fuzzy element name matching ('product_id' in XML/JSON will match C# property named 'ProductId')
- Automatic detection of type of content returned
- GET, POST, PUT, HEAD, OPTIONS, DELETE supported
- Other non-standard HTTP methods also supported
- oAuth 1, oAuth 2, Basic, NTLM and Parameter-based Authenticators included
- Supports custom authentication schemes via IAuthenticator
- Multi-part form/file uploads
- T4 Helper to generate C# classes from an XML document
http://github.com/restsharp/RestSharp
or
http://restsharp.org/
similar - http://www.nuget.org/packages/Microsoft.Net.Http/