Thanks for your suggestion, I will have a look on MobMuPlat as soon as I have some free time. But for this project of mine, it is really not the correct tool to use. I am currently making a research involving object tracking and right now I am using iOS for this project only because I own an iPod Touch myself, but the final idea would be to propose a self sufficient kit with a GPS and gyroscope sensors using a x-OSC board or an Arduino board.
MobMuPlat looks very interesting and powerful, but it is something that would require time to understand (as opposed to a simple app that only sends OSC messages), and since in the end none of these things will belong to the final project, I just need an easy and immediate solution (that app that I posted above looks just like that, but I still didn't have a chance to test it).
Thanks once again and take care!