Firgured linking the April print copy to the app would promote the print issues as well...so checked out the colour sequence of the April issue cover and cover shoot images.
A very interesting example would be the Augmented Reality November issue of Esquire magazine. Simply done for marketing the magazine, does not however impact the readers in anyway. It's just the interactivity that makes it interesting. Readers buy the issue only to find out what augmented reality is and how it would work as its still a new concept.