Fans robotics and the professionals of this field are in luck, since the boys of makeprojects.com have posted a guide for connect an iPhone to a Arduino, without any jailbreak.
For those who do not know, Arduino is a platform of free hardware And, although for me, with limited electronic knowledge, it is difficult to explain, I suppose those with knowledge in the subject will be delighted with such an excellent tutorial.
You can see it on the page Make Projects
free hardware… is it free?
With free it means that everyone can contribute to its development and its specifications are open. Obviously Arduino is not free, being hardware you need physical components that you have to pay for. You cannot equate (literally speaking) the definition you use for free software to that of free hardware.
The idea is good…. But the ideal would be to be able to program the arduino using the iphone or ipad ...
To use the iPhone with Arduino, it is better to use the touchosc app and processing ... Give more play ...
I have done something that you can see in http://www.lisergio-z.com