OData Services - SAP Backend and Non-SAP Backend - Same App

Experts currently we are working an iOS App. We are on SMP3.0. Our client has RFC's in SAP backend and some SOAP services. We have writeen OData services for SAP backend RFC's and for SOAP services we have used IGW. My question is if I want the collections(collection names) created in both SAP backend & non SAP Backend OData services under one App. I mean under one endpoint url all the collections should fall into. Can anyone please help me on this.

Regards,

Deepika.