PDa is a port of Pure Data that runs on Personal Digital Assistants (PDA's), made by Günther Geiger. The hompage of the project is http://gige.xdv.org/pda/.
It should be relatively straightforward to build lots of the non-DSP externals for PDa/ARM. The key part of this project is to create the framework for building PDa-extended, every object does not need to be ported. Once the framework is created, then the porting of objects can happen incrementally as people need them.