Get UDID of iPhone or iPad by single tap without iTunesGetUDID.io uses Apple Mobile Device Management to provide you information about your device. Profile you install tells your iPhone, iPad or iPod to send encrypted data (UDID, IMEI, Serial No, & etc) to your browser. This profile is temporary and exists on your device only for a few moments to send encrypted data. After this profile removed from your iOS device. We do not store or reuse any of your device information.
To check if there is any profiles installed on your device you check on your iOS device Settings->General->Profiles. If there is no such section then there is no installed profiles on your device.
Apple allows to get UDID, IMEI, Serial No., Product Name and iOS Version. GetUDID.io provides all this information to you and doesn't get access to anything of this.
You can use your UDID to allow iOS-developers make apps for you and to get access to beta versions of iOS.