If anyone is more interested in Realm's strategies, you can see the articles and videos they host at https://realm.io/news/ where most of the content is guest content.
They perform professional-level video recording of many conferences and publish the videos, complete with transcripts, as well as hosting simple blog articles. These are all mentioned in association with their @realm twitter handle as well as Realm's own announcements.
I think they have had at least two people doing this full-time since early days, at least a couple of years.
This is in addition to their own conference and expo booth presentations.
They also host 1 or 2 regular meetups in their SF office.
This is the kind of marketing you can do when you have raised $29M but note the discipline and vision to start doing this relatively early, establishing themselves particularly in the iOS development space as a centre of excellence. Thus, they get people following @realm.