A quick way to collect the UDID on an iOS 7 device is to navigate to a website through Safari.
The following steps explain how to collect the UDID from the device:
1. Navigate to http://get.udid.io.
2. Click the "Tap to find UDID" button on the webpage.
3. Click the "Install" button on the "Install Profile" page and input the corresponding passcode for the device if one has been enabled.
4. Review the UDID when the safari page comes back to the foreground.