# Introduction

The [NextBillion.ai](http://NextBillion.ai)’s iOS Nbmap Maps SDK allows users to integrate regional offline map packages in a Swift application. This comprehensive guide covers SDK configuration, accessing & using region catalog, download progress, update handling, offline map display, and troubleshooting.

## Prerequisites

Before integrating regional offline maps, make sure that:

-   The application adds the `Nbmap` product through Swift Package Manager, or links _Nbmap.xcframework_ using another supported integration method.
    
-   A valid NextBillion Maps API key is configured.
    
-   The regional offline service provides a region catalog, region details, regional packages, and shared preview resources.
    
-   The application can display estimated download size and handles insufficient device storage.
    

_To use offline Maps for offline navigation, refer to the_ [**iOS Offline Navigation Integration**](https://docs.nextbillion.ai/routing/ios-offline-navigation/introduction) _guide._