I have not been able to determine if there is either. I exchanged a few emails with Jim. Judging on this short dialog, I don't think that there is a pda version.
Jim was pretty clearly in favor of verified drop charts, and for sure down on the watered down software that is run on hand held devices. Also seemed skeptical of the efficiency of toggling between screens to get the information that should be included in a drop chart. Probably has some experience with the average uninformed Joe, assuming that his new software will spit out 100% hard data that can be relied on for 100% of shots fired regardless of field conditions. I would be leery of advising such a course to just anyone as well.
I directed him to this site, referencing the success stories of some of the members here using this method to great success. Maybe someday he will come out with something for PDA's.
It would really be nice if someone were to develop something for the iPhone, It really does have the nicest interface, and it would be awesome to be able to use it with a ballistics program, especially since it is designed to automatically sync with the PC when it is plugged in. It would be great to be able to automatically add the data you developed at the range just by plugging in the phone. Imagine updating all your charts automatically for new conditions. I guess its only a dream for now.