You need to pass your UDID onto iPhone developers, if you want to beta test their software. To access your UDID, plug iPhone into your computer and bring up iTunes. Then, click on your iPhone under devices. Next, click the serial number, and the UDID will be displayed. From here, you can copy using Command + C or Control + C. I tested this MacOS, but not Windows. However, I am pretty sure it would be the same procedure. I would suspect that the same procedure applies to iPod touches too, but I do not know for sure.