Edit Form Columns for a mobile list view on a Sharepoint List using PowerApps forms on desktop

I have a Sharepoint list using PowerApps forms on desktop, which works well.

However, on mobile (in the Lists app) the form is the default SharePoint form. This is fine, but how do I edit the form columns for the mobile view?

The normal 'Edit Columns' button/menu to do this within SharePoint is hidden by PowerApps on my computer and doesn't seem to be there at all on mobile. What is the workaround to access this feature?