Realm .NET
The C# API of Realm is incredibly simple because it leverages the power of LINQ for querying and the Fody weaver to transform plain C# class declarations into persistent objects.
The main classes you will use are:
Helper classes you may use are:
Querying and Sorting are provided on a Realm using standard LINQ syntax including Where and OrderBy.
To see what is supported, refer to the LINQ Support page.
Realm Overview Diagram

Documentation
The documentation can be found at realm.io/docs/dotnet/latest.
The API reference is located at realm.io/docs/dotnet/latest/api.
Source
Source is available on Github.
Instructions on how to build from source are included in that repository's README.md.
Problem reports and Feature requests
The github issue tracker can be used to report problems or make feature requests.