This app utilizes a service worker to allow for offline viewing and asset caching It utilizes the News API to display current headlines to the user, and if the user is offline or otherwise has no access to the network, the user either sees a message telling them to retry once they have internet access, or allows them to continue to view news headlines that the network has already received and put into the cache.
Check out the demo and play around with your connectivity to the internet so that you can see how it all works.