Started with the source code of the applet provided by MandelBox370:  https://github.com/rudi-c/mandelbox370
Made an iPad rendition, then slowly starting adding more parameter controls.
Just added a 'cross-eyed' 3D mode, which from certain views provides beautiful vistas.
If you like writing programs for your iPad, please take a look: https://github.com/Kosalos/MandelBox