The difference between RelatedTo and RelatedToVia in Spring Data Neo4j is that RelatedTo refers to the node-entities at the other end of a relationship, while RelatedToVia refers to relationships themselves as relationship-entities. There isn't a built-in facility for "supernode" relationship navigation, but indexing relationship-entities can be used to write an index and retrieve specific data using GraphTraversal and TraversalBuilder. Embedded Neo4j databases cannot be accessed by multiple applications simultaneously due to the limitations of single-JVM access, requiring alternative protocols to be exposed on top of the database for interaction with other processes.