It's not a container at all. We leverage a plugin that provides a JSON representation of the Wordpress site content.
We consume the JSON to display the Wordpress content within a fully native UI and give access to all the speed, features, and benefits that a fully native app has to offer over web or hybrid apps.
Assuming this is one of the standard JSON plugins for wordpress, be cautious of what this may do to the main sites load. The default install can force calls to skip the total-caching plugin most sites use, as it wont use the cache on any request with parameters.
This looks like a container similar to PhoneGap, but more specialised to some sort of feed from the WP website, perhaps RSS.
Is there really that large a market for this sort of thing?