yeah the group focus works fine on mobile because its closer to the top of the page and the repeating group is not too long.
I disabled showing the group focus (for mobile) on this demo because the group focus was too close to the bottom of the screen and ios keyboard would push it up (covering the input).
I think its best practice to have a second screen for mobile where the input and repeating group start at the very top (when searching).
I will implement this by weekend hopefully.