invitations_controller.rb

class InvitationsController < Devise::InvitationsController
  
  include Devise::Controllers::InternalHelpers #not sure if this is necessary

    # POST /resource/invitation
    def create

      #Assuming the user_id of the gifted user is = 1
      if current_user.id == 1
        current_user.increment!(:invitation_limit)
      end
      
      super
      
    end

end