IOS OTA installation : capture .ipa file instead of installing

Question

I want to direct-download an .ipa file instead of going through itms-service and installing the file on my iPhone. I cannot access the manifest .plist file because it’s dynamically made by PHP and disposed after the installation.

I tried changing safari user agent to iPhone so that it might download the file itself, but safari can't figure out what itms-service is. Is there anyway to capture and save the .ipa file with my iphone instead of installing it?

I've already tried file_get_content the with PHP and going through the installation with a download manager on my iphone none of them was working.