I just downloaded Barneys Newyork application made with DPS Solution and wonder how Segal Savad (the studio that made the app) attend to build the intro effect of that application ?
Basically the launch of the app comes directly into a two-articles folio (animation/navigation instruction) instead of going directly to the top collection.
This behaviour is nice and gives some pretty good ideas here
The two articles you see are likely the two articles in the top-level collection. There's no way to make a DPS 2015 app do anything other than open the top-level collection on launch, so it's likely the intro stuff you're seeing is simply an article that's the first item in the TLC.
It's also possible that they're using in-app messaging with Adobe Analytics to do a first-launch in-app message using HTML. To do that requires purchasing Adobe Analytics to use with DPS.