One of the focus area for us when developing the new Oracle Application Builder Cloud Service (ABCS) was to create a tool that would make it very simple to enrich Oracle SaaS applications.
This integration is a key part of Oracle's PaaS for SaaS offering - where we have unique capabilities in our Platform as a Service offering for our Software as a Service customers.
With ABCS it is very easy to pick up objects from Oracle SaaS (through the built in service catalog) and then design new web and mobile interfaces that show data from those.
In addition you can then add your own custom fields and related objects with additional data you want to track.
Once your application is complete - you can then either run it as a stand-alone app, or embed it into an Oracle SaaS interface.
I wrote two blogs and recorded two videos that show you the basics.
Embedding Oracle Application Builder Cloud Service Apps in Oracle Sales Cloud
These videos are part of the new Oracle Application Builder Cloud Service YouTube Channel
And the blogs are published on the Oracle Application Builder Cloud Service OTN Community
We have more tutorials there to help you go even further - so check them out!