In my world there are only 2 fractal programs: Apo and UF. I know that that are many other programs out there with many faithful users of those programs, but I don't care. Xenodream is about the only other program that has gained enough of my attention to maybe give it a try, but I don't want to go though another learning curve, so there are only 2.
I learned to use Apophysis 1, which was designed by Mark Townsend to be a front end flame finder for Ultrafractal. As far as I am concerned, Apo has always been a front end flame finder for UF and it always will be. I have never had much use for it as a standalone program.
With that in mind, the controversy of which program is better is irrelevant in my mind because they are tools that are to be used together. It like saying which is the better tool between a mouse and a keyboard, or which are the better keys on a piano, the black ones or the white ones.
Apophysis flames inside of Ultrafractal open up a world of creative opportunity. Instead of working with just one flame, many flames can be colored and combined to create a composition.

The trouble is that Apo and UF no longer work well together. When Mark turned over the program to the "Apophysis development team", the team was less concerned about UF compatibility and more concerned about improving Apo functionality. That's understandable. As Apo progressed, the UF formula writers needed to update their formulas to keep up with the changes in Apo, and they did for a while.
The people who use Apo and UF the way that I do are beggars in this scenario, not givers. The flame formulas in UF are way over my head so I have to depend on others to keep them compatible with Apo. We have to depend on the Apo developers to care about UF compatibility enough to ensure that the UF formulas can be updated with minimal impact. We have to ask to keep them working together, and in the past we have, but I haven't heard anyone say anything about it for a few years.
Don't get me wrong. I am not complaining. I am a beggar so I have to take what I am given and keep my mouth shut. I am grateful for the efforts that have been put into both programs.
However, I am saddened by the loss of creative opportunity that occurs when these programs stop working together.
For me, the ultimate version of Apophysis would be one that is specifically designed to be compatible with UF. The ultimate Apophysis development team would see the value of UF compatibility and release updates concurrently with corresponding UF formula updates.
One can dream...