I'm posting this workaround that we found and implemented in our project. The work around for us until apple fixes the issue is after the call to .addOverlay of the polylines we do (our map is on .standard normally): mapView.mapType = MKMapType.hybrid mapView.mapType = MKMapType.standard The switch is not perceivable, but makes the map flicker a little, but more importantly it seems it clears the app cache and stops the whole map and app from freezing. See source: https://stackoverflow.com/questions/69248520/vkdefault-triangulator-failed-to-fully-triangulate-polygon-mapkit For the beefier numbers of polylines we had to reduce the number being added as even with the workaround some big numbers were still creating freezes.

This issues seems to have started with 16.1.

To be even more precise, this issue started with iOS 16.1.

Seems that we always get this before the crash: [VKDefault] Exceeded Metal Buffer threshold of 50000 with a count of 51635 resources, pruning resources now (Time since last prune:31.189292): Assertion with expression - false : Failed in file - /Library/Caches/com.apple.xbs/Sources/VectorKit/src/MDMapEngine.mm line - 1363