Thank you for reporting this issue.
Yes, you are correct.
The Theme Options -> PAGE TITLE BAR -> Parallax Background Image ( setting )
only works on desktop and does not work in mobile Safari
This URL http://creating.essentialyogaschool.com/about/
has the page title bar parallax background and it works on desktop,
but in mobile safari it does not.
It’s beyond my knowledge to provide a solution for this issue.
I will report this issue to my employer, hopefully the developer is able to find a solution for this issue.
Please wait for next available version update.
Thank you for your patience.