The way Apple has set up for developers to send their applications to users for testing before submitting to the App Store for general consumption is built around the idea of provisions and device IDs. Fortunately for you, dear user, you only need to worry about the device ID part (trust me, you don’t want to know).
Locating a Unique Device ID with iTunes 7.7 or later
You can find out your device’s UDID using iTunes 7.7. or later. To do this, connect your device to your Mac and launch iTunes. In iTunes, select your device in the ‘Devices’ section and navigate to the Summary tab. Click on the Serial Number label to reveal the Identifier field and the 40 character UDID. Press Command+C to copy the UDID to your clipboard.
Note that you do not need to highlight or select your device ID, simply Command+C when the ID is being displayed.
Now just email this long text (it is 40 characters of lowercase letters and numbers) to the developer who requested it, and await your preview version!
[Instructions originally from developer.apple.com]
Are there any security risks by sending this?
Nope. This is Apple’s officially sanctioned method for distributing samples.
