At Field Nation, managing view state, in the #iOS app, became a challenge when we added multiple asynchronous actions and multi-stage work order completion.
ComponentKit's React-inspired approach to building UI made layout declarative, functional and more composable. Plus, as an Objective-C++ framework, there isn't the typical trade-offs of layout speed and compute overhead. In fact, you'll get background thread layout and view recycling for free. It was easy to implement and fully test complex UI interactions like checking in to a work order, receiving location-based alerts, and uploading deliverables. Additionally, CK provides an escape-hatch, for advanced views, to drop down into UIKit or CALayer. The outcome is the flexibility to incrementally migrate views and maintain delightful layer-based animations.
Overall, CK makes it easier to build a view hierarchy, snapshot test all possible states and efficiently manage views. Less bugs, happy designers. The trade-off is the ramp up on component-based software engineering.