Every time the interface loads or changes, the Watch and iPhone communicate round-trip over Bluetooth. Whether due to wireless flakiness, 1.0 OS bugs, or (most likely) both, WatchKit is frustratingly unreliable. Apps or glances will sometimes just spin forever instead of loading, and even when everything’s working perfectly, apps still take so long to load and navigate that the watch’s screen often turns off before you’ve accomplished anything.
This is by far the biggest annoyance with apps on the watch. More often then not, the screen turns off before the app finishes loading.
This article is about the podcast client I use every day. It is an amazing app, and is now much more worthwhile on the watch, too.