Marketing it is. I actually thought about this idea for a long time, and did a design based off of the phonebook in iOS 11. But marketing this application is n

Marketing it is. I actually thought about this idea for a long time, and did a design based off of the phonebook in iOS 11. But marketing this application is nearly impossible, because it doesn't have any extra features. It just has phone numbers [contact details], and that doesn't excite users to spend time getting it set up. So I concluded that this is something that has to be done from the OS vendor side. We need an extension to the CardDAV protocol, and we need vendors to implement it.