Why are there two story map platforms with separate authentication accounts?

[akoleavisual]

Hi, Pretty new to the platform. Im curious why there are two platforms for story maps? I downloaded the mobile app and tried to sign in, but was prompted to sign up. I realized later that there are 2 unique systems running what appears to be the same exact platform. 

The one I signed up with accesses via my url.maps.arcgis.com the other is https://storymaps.com/stories

What are the advantages/disadvantages to these two if they are. On the pricing for the storymaps.com page it lists more publishing options than are available via the arcgis.com url platform.

Would I have to subscribe to the storymaps.com platform to get the features listed there? 

[OwenGeo · Accepted solution]

@akoleavisual -- Hello, please see this page, which describes the difference between ArcGIS StoryMaps and StoryMaps.com.

Storytelling Solutions for Professional or Personal Use (esri.com)

In short, the decision about which product to use is not a list of advantages or disadvantages of each one that you'd evaluate; rather, the choice is dependent on whether you are creating stories as part of your job/profession or for personal reasons.