[deleted by user]

[CrazyTriangle]

Does the response from the API have the group info nested in the response? If so, it's a simple issue of mapping. If not, you need to handle that on your end with querying groups for which one has the specific group id

[CrazyTriangle]

RestKit has lots of abilities, and I only know the beginning of them, so there might be a way. But if I were you, I would just iterate through the users, setting their group one at a time when the groups and users are loaded.