Hey, PSPSeq creator here. Hadn't checked around for a few months to see if there was still any PSPSeq chatter in the world and found this. Nice to see a couple familiar names. I haven't worked on the program for quite a few years now but when I listen to the tracks some people made I'm happy with what I created; just wish more people had jumped on it.
As for the controls; yeah I know how they work and find them fast and intuitive but I wish I'd had more testers of the UI at the beginning since my opinion is in the minority here. I think one key thing people miss is that the left and right bumpers can be used to change the rate of various controls. Left bumper makes changes go way more slowly, right bumper way faster. The D-pad is generally used for very precise changes and is also used in conjunction with the L/R triggers.
The other controls I think people miss is when you're in the synth editing menu where you see all the gen/fx/env parameters. There's a few cool things you can do from there. First you can control a single parameter for all steps, either locking them all to the same value or keep their relative values but sweep the whole lot together. You can also do some interpolation of control values and randomization of control values.
There's a 1 page cheat sheet for all the controls in PSPSeq that comes with the download. Here's a link to it directly:
http://www.dspmusic.org/psp/PSPSeq301QuickReference.pdf
Definitely try and understand what everything means on this page. There's a lot of things you can do that aren't immediately obvious but let you make some really interesting sounds pretty quickly and take the UI from crazy twitchy to fast and precise.
I may still write an audio app for a mobile. I actually started working on a Java port of the PSPSeq synths so I could run it in Android but the audio story on that platform is so bad I kind of lost motivation. Also I just started a new job (at Beats by Dr Dre) and they are keeping me seriously busy so no time for fun music projects other than the ones I'm doing for my job!
If anyone has any questions I'm happy to answer; I may even do so in less than 6 months!