Most of theses Fractal Arts are worked with ArtMatic.
I started with ArtMatic 1.2, and I play with it time by time
and it's so easy to use and I enjoyed very much.

Now, I have ArtMatic Pro 4.1 and it become more powerful & complicated.
I still can not handle it well, but it can be create 3D images as well, and
it helps endless to create variety of Fractal images.

ArtMatic is for Mac user, but I also found some other applications
including free soft for Windows such as Apophysis, Ultra Fractal,
XenoDream, KPT Effects (Hybrid), etc. etc….