iPhone开发FOR越狱设备（不使用越狱设备！）

I would like to dig into developing for jailbroken devices, just to test what the device could do. I would like, for instance, to alter the ipod music based on geo-location, so i have to program a new daemon that runs in background and fetch gps informations at regular interlavs and then make something with them.I would like to dig into developing for jailbro