Clever. To build an app, Buzzfeed first built an enewsletter and tested that: "Designing and building an email newsletter takes a lot of work. But compared with launching a native app, a newsletter requires a much smaller investment of time and technology. As a lower-stakes product, we could launch it much more quickly than we could an app and …

"nearly 67 percent of emails were opened on a mobile device... it’s not that hard to create responsive emails. ... Here are 10 quick design hacks" - 10 design hacks for responsive emails that don’t suck

"when an email newsletter, which looks look superb on desktop, fails to render properly on a mobile device, respondents either hit delete or unsubscribe." - Responsive Email Design: Benefits, How-To, Examples + More | JUST™ Creative