Developing for Apple Watch, 2nd Edition

Performance Concerns

The most fundamental differences between WKInterfaceTable and UITableView relate to the way row content is set up. The interesting thing about WatchKit’s approach here is that it’s in direct contrast with the way iOS does it, and yet UIKit on iOS works the way it does for performance reasons. You’d think the lowest power device—Apple Watch—would have the most efficient API for table performance, but the needs are quite different.

The WKInterfaceTable API remains virtually unchanged from watchOS 1. You may recall that in WatchKit for watchOS 1, every time a method is called in your WatchKit extension and the watch UI is updated, Bluetooth communication is happening between the watch and the phone. If WKInterfaceTable ...