A session controls how data is synchronized between a single Realm on the device and MongoDB on the server.
A session is controlled by Realm, but can provide additional information in case of errors. These errors are passed along in the ErrorHandler.
When creating a session, Realm will establish a connection to the server. This connection is controlled by Realm and might be shared between multiple sessions.
The session itself has a different lifecycle than the underlying connection.
The SyncSession object is thread safe.