How to Find UDID of iPhone or iPad without Mac or PC
Step 1. Open Safari on your iOS device and head over to https://get.udid.io/
Step 2. Click ‘Tap to Find UDID’. Press Allow when you’re asked to install a Profile.
Step 3. Go to Settings. At the top, you will see ‘Profile Downloaded’. Click on it and follow the instructions.
Step 4. You will be automatically taken back to https://get.udid.io/ but now you will see your UDID.