Change comment button from BACK to COMMENT or other intuitive icon

Request to change the UI on iOS to use a standard comment or chat or bubble or other icon for comments, moving away from the current Back button. New users to mastadon are left unable to comment on posts unless they accidentally click back on a post and realize it’s not back but comment. I’ve seen several posters have guests who are not participating at all because it appears in common usage that the back button, which seems to intend to mean Reply (though replies imply one to one) is meant to be used for commenting.