In this section, we will look at compiling and running our Shopping List application. Since Apple Pay supports only non-bank issued American Express cards, we will be running this within the WatchKit Simulator:
To run the app, select the ShoppingList WatchKit App scheme and choose your preferred device from the iOS Simulators section, as shown in the following screenshot:
The preceding screenshot shows you the process when a product has been selected from the WatchKit extension and communicated with the iOS device. Since we have requested to have a shipping address as a requirement, you will notice that the SHIPPING ADDRESS REQUIRED text appears in red. The Shipping Address info with an exclamation mark prevents the user from progressing further, until they have provided this information:
As you can see from the preceding screenshot, using the PassKit and the Watch Connectivity frameworks, you can allow your users to make purchases directly...