When that entry is viewed in Flipboard, it looks a bit problematic (see top right hand entry on this screenshot):
Flipboard tries to populate its social media layout with images by aggressively looking for the first image in any link in a post (it has its own rules for how it does that) and it is finding the image referenced in the index,html file (images/swipeStart.png in line 98).
I retweeted a link to this app: http://www.arcgis.com/apps/OnePane/storytelling_basic/index.html?appid=36f2000dce204295a3e3a0e88f88d0de on the EsriStoryMaps twitter feed (https://twitter.com/EsriStoryMaps)
When that entry is viewed in Flipboard, it looks a bit problematic (see top right hand entry on this screenshot):
Flipboard tries to populate its social media layout with images by aggressively looking for the first image in any link in a post (it has its own rules for how it does that) and it is finding the image referenced in the index,html file (images/swipeStart.png in line 98).