I'm organizing a in person seminar with limited seating and wanted to promote it by not showing the names of registrants, but the company names.

Most subscription based apps only can display the first name of the person and the location.
Others claimed only to be able to do it at top level subscriptions plus other hoops.

Proven.ly on the other hand is super easy to implement and gives me complete control of the messaging. Perfect 5 stars for my needs.