Just like David Rockerfeller's Rolodex! https://news.ycombinator.com/item?id=15867741 I've always wanted to create something like this myself. Glad to see someone do it.
I made my own solution to this 6 years ago and use it to this day. my solution leverages google people api so it’s automatically synced as part of the notes field of my contacts, and I have an app in my iphone and on my desktop and a cloud interface to quickly manage and query the data.
10/10 recommend and wish it was more normalized