It would be great to have a direct menu option on the mobile app to collapse and expand levels. I noticed a similar function on other app. See the menu option! 20210324_181910|387x500
It’s the + icon on the right side of each node.
That is expand/collapse but OP is asking about this:
Only the first is available.
The option that you mentioned is for the windows version. I am refering to the android version. The android version does not have the option to expand and collapse as the option for the computer.