Super weird that they didn't mention it in the docs. In the source code, they mention they will be taking it out in a future release:
NOTE: In 1.2 of the Google Maps SDK for iOS, these methods are deprecated. They may not appear in later releases of the SDK. Instead of using these methods, we suggest that you maintain your own references to overlays that you have added to a GMSMapView.
Seems like they're moving the onus onto us as developers to keep references to added overlays. I do that in my app by creating a NSMutableArray
of addedMarkers. Every time I add a marker to the map, it's added to the array.
I assume you could do the same with polylines and ground overlays. Each of those are their own class so it shouldn't be hard to group them and identify them later if you need to.