Not sure if you guys are into music software for portable devices.
I definitely recommend the following…if you can use renoise, it will be easy to learn these:
MILYTRACKER (PDA):
http://milkytracker.titandemo.org/downloads/
Its Fastracker 2 in the palm of your hand…good for getting creative with single cycle waveforms.
(which can be generated or hand drawn in the program itself, use 64 or 128 samples in length for perfect tuning)
SUNVOX (windows, mac, linux, ios, android, pda):
http://www.warmplace.ru/soft/sunvox/
A great tracker software which focusses on synthesis and sound design in a modular environment…Its a little like Pure Data in a way, but easier to use.
G-STOMPER (android):
http://www.planet-h.com/g-stomper-studio/
A very nice electribeish sampling drum machine with automation and effects plus a great synth with sequencer called VA-Beast.
LITTLE GAME PARK TRACKER (PSP):
A very unique tracker similar to early C64 trackers in that it uses tables to create timbres, intricate arps etc…very much like renoise phrases at 1LPB at extreme high BPM…it has a wave scanning command for morphng textures. Particularly nice with a sample called MONOWAVE.wav.
http://littlegptracker.com/download.php
The monowave sample is downloadable from here:
http://hexawe.net/compos/monorave/
You will need half byte loader from wololo.net to run Little Game Park Tracker (as it is non-official PSP software, unlicensed by sony)
Get it here:
http://wololo.net/hbl/
These are all great because you can go to the park (or on a road trip or something), work on music all day without being stuck in front of your computer, then come back and load up all your work into renoise for further structuring and tweaking, arranging.
Also for more advanced sound designers, Pure Data might be worth a shot, but if I’m honest its too advanced for me for the moment…steep learning curve.
https://puredata.info/