问题
Given the iOS Address Book API, or possibly other App Store friendly APIs, is it possible to find the user’s contacts that also use iOS? The only heuristic I was able to come up with was finding all contacts that have a kABPersonPhoneIPhoneLabel phone number – but that method has a lot of both false positives and negatives.
回答1:
This is now possible using CloudKit and the CKDiscoverAllContactsOperation class. You only get the user’s contacts that also use the same app and have given an explicit permission, but for some use cases it’s a nice start.
回答2:
your heurisitic might be ok but it relies on the USER correctly setting that attribute.
depending on the context it might be good enough / or not .. dont know.
there is no real way to detect which user really uses ios (no API)
来源：https://stackoverflow.com/questions/22509022/is-it-possible-to-find-user-s-contacts-that-also-have-apple-devices