One of my most popular conference presentations is the development tools comparison. I've been giving this in various forms for almost 20 years, and will be giving it again at the OUGN Spring Seminar next month. Oracle keeps putting out new development tools, keeping the topic as relevant as ever.
The "big three" Oracle tools out there right now is the venerable Oracle Forms, just out in release 12c, Oracle APEX and Oracle ADF. I follow many projects and discussions with all of these tools, and the latest Google trends report pretty well matches what I see elsewhere:
(the blue line is Forms, the yellow is ADF and the red is APEX).
You can see Oracle Forms declining slowly and leveling off at about the same level of interest as APEX and ADF. So from the perspective of developer mindshare, either of these three tools is fine. There are of course many other considerations - if you want to learn more, come to my talk at OUGN next month or in June at KScope16 in Chicago.