Choreographer lets apps to connect themselves to the vsync, and properly time things to improve performance.
Android view animations internally uses Choreographer for the same purpose: to properly time the animations and possibly improve performance.
Since Choreographer is told about every vsync events, it can tell if one of the Runnables passed along by the Choreographer.post* apis doesn’t finish in one frame’s time, causing frames to be skipped.
In my understanding Choreographer can only detect the frame skipping. It has no way of telling why this happens.
The message “The application may be doing too much work on its main thread.” could be misleading.