You can also use alternative map sets, for example, the Nutiteq Maps SDK: http://developer.nutiteq.com , standalone maps for iOS (and Android), supports the Xamarin IDE (C #) and native languages ββ(ObjectiveC, Swift).
It is more focused on professional applications and complex maps with interactive layers (points, lines and polygons on top of maps), you can even add 3D objects to display. One of the advantages is that you can use your own sources of the base card (your own, third parties), and not just the OpenStreetMap that the SDK itself provides.
Disclaimer: I'm a developer.
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