The mobile app should show you any relationships the assigned task has. This system was marketed as being able to use relationships to link different lists, that way data doesn't have to be repeated. I have a list for clients, i have a list for projects, the tasks of those projects are related to a client. However, there is no way to know who the client is if i am looking at a project task in the mobile app as relationships are not there. Relationships are a great feature, but they should have been available across all platforms used.