How to create TestApp.ipa file for iOS browser using mac

Hello,

I am following above video to setup for iOS(iPhone) browser testing using macbook. I followed all steps till 5:00 but on 5:00 minute in video it showing TestApp.ipa. Can anyone explain me how to create TestApp.ipa? what is meaning of TestApp.ipa file?

Please answer me. Thanks in advance.

Thanks
Rakesh