There's Rjdj, which basically runs pd patches without gui (calling them "scenes") giving you the possibility to use the smartphone's touchscreen and accelerometer as controllers for the patches. So, you still need your pc to edit patches, but you can "use" them on the phone. Rjdj is for iphone, but you can download an rjdj scene player for android devices here:

http://puredata.info/community/projects/software/sceneplayer

or here:

http://autobuild.puredata.info/pdlab/libpd/

At the second link you will also find an archive with some rjdj "scenes" and Pd Test, it should be something similar to scene player but honestly I couldn't understand how to use it, i can just test sound (maybe it's intended just for that?). Here are some resources on how to build pd-patches for rjdj/scene-player.

>From the rjdj blog:
http://blog.rjdj.me/pages/pd-utilities

A tutorial by mike dixon:
http://blog.makezine.com/archive/2008/11/howto-hacking-rjdj-with-p.html

Both are iphone-oriented, but they contain very useful informations on how to start. Other resources:

Some example scenes (very good base to learn):
http://download.rjdj.me/pdutils/examplescenes.zip

Rjlib, a collection of useful abstractions to build your scenes, and the abstractions you need to run a scene in pure data on a pc:
https://github.com/rjdj/rjlib

Pd everywhere, on noisegroups. Here are some interesting discussions about this topic, like the following one:
http://noisepages.com/groups/pd-everywhere/forum/topic/sceneplayer-for-android-vs-rjdjs-scene-player/

I just started to deal with this stuff, and i have still many doubts and difficulties. For example, i still couldn't understand how to download scenes from the rjdj website on my android phone, it seems you just can do this with an iphone. I hope anyone reading this thread has some useful hints :)

athos