[smithclay]

Couple of companies come to mind:

* Realm.io has successfully positioned themselves as a thought leader in swift development for iOS by producing solid blog content and leading the Swift SF meetups (+ contributing to open-source projects).

* Crashlytics/Fabric.io is more interesting -- my experience with them has been entirely word-of-mouth (but they have a big presence at Twitter's developer conference/WWDC/Google IO, too).

* Parse generally has interesting, high-quality technical blog content: (https://blog.parse.com).

[NateLawson]

I agree that both Realm and Fabric have done an excellent job reaching out to developers. Fabric went to another level in providing a slick interface to make it easy to drop in and update their SDKs. I'd be excited to see that more generally available, maybe integrated with CocoaPods.

[coldcode]

My only fear with Fabric is how Twitter's layoffs affected them.