Join Bill Weinman for an in-depth discussion in this video About app extensions, part of iOS 9 App Development: Extensions.
- iOS app extensions are used to extend the capabilities of an IOS app beyond the scope of the app itself. An extension is a separate executable that is delivered as part of the application bundle with your app. The app that contains the extensions is called the Host App. The Host App provides context for the extensions and often shares code and data with its extensions. There are a number of different types of app extensions called Extension Points.
In this course we'll be focusing on the most common types. Today extensions are used in the Today View of the notifications center. These are very common and very handy. They can provide a quick glimpse for your users giving them useful information without having to interrupt their workflow to open the host application. Share Extensions are used to share data with social media sites or other online resources. iOS provides a number of useful share extensions or you can write your own.
Application Extensions seen here on the bottom of the share sheet are used to view or manipulate content in another app on the device. A common use for action extensions is to open a web browser or another app to handle a piece of data. iOS provides extension points for a number of other purposes that are not covered in this course including photo and document editing, custom keyboards and Apple Watch extensions. In this course we'll be focusing on the most common types of extensions; today extensions and action extensions.
The techniques you learn here will also apply to other extension points.