New to iOS 10 is deep app integration with Apple's Messages app. The process to add a third party's functionality to Messages isn't a one-click process, though -- here's how to do it.
Find your app
The iOS App Store labels each app clearly with compatible platforms in both iOS and macOS. After identification, the purchase and download process for a Messages app is unchanged from an iOS-only app.
After download, by default, the app is not added to Messages. We can fix that, though.
Adding Message hooks
Once the app is installed in the phone, it still needs to be added to Messages. Tap on the App icon in Messages. Following the tap, invoke the Messages management dock by tapping on the lower left corner of the screen.
The Messages management dock gives icons for already added apps, as well as a direct link to the Messages store -- Messages compaible apps can be added from here as well. The "Manage" tab is the next step.
We recommend users enable the "Automatically Add Apps" if you only need a few apps. Apps can be toggled discretely for inclusion in the Messages management dock, the same way as features are toggled in iOS settings.
This is the same screen to cut hooks to Messages apps. If the functionality of the app is no longer needed, it can be disabled from this screen. Hooks to Messages and inclusion in the Messages app tray are removed automatically if the app is deleted from the device as well.
Using the App in Messages
Once the app is in the tray, a single tap to invoke the tray, and another single tap to open the app is all that is needed. Dynamic data apps, like the ESPN app as well as more static features, like sticker insertion into a message are both handled from here.
Messages, today and tomorrow
Apple's new Messages implementation is an incredibly rich communications method. Unlike other implementations, the Messages App data inclusion or sticker application doesn't need all of the parties in the conversation to have the relevant app to use the unique features that app integration brings.
Since launch, the number of apps that support Messages, even if only with decorative stickers for adorning conversation has increased exponentially. The volume will only keep growing, and the potential of developer extension of the platform is immense.