I think I wanted to write a few lines about APEX and VBCS (Visual Builder Cloud Service).
So APEX and VBCS are both Oracle products made to create custom enhancements or also standalone products in the oracle universe. While APEX has been around for a while already, VBCS is kind of the new kid on the block. Both are low code and offer a framework for rapid software development. So what's the difference ?
Apex comes with your Oracle database for free, whereas VBCS is included in the Oracle Integration Cloud and comes at a not so cheap price.
APEX lets you create a database application by directly accessing the database and creating forms on top of data views. Even if APEX meanwhile supports REST based development, that's where VBCS excels. VBCS is made to enhance cloud software by enabling developers to directly create forms based on rest interfaces and as a bonus it is neatly integrated with the oracle developer cloud allowing for lightweight and quick CI/CD processes. Altogether, if you want to create a database application, or want to enhance your on premises Oracle application you would typically use APEX. If you want to enhance your Fusion Cloud and use OIC to integrate with your environment anyway, VBCS is the tool you want to use.
Hope that gives a quick overview