When comparing Prismatic vs The Old Reader, the Slant community recommends The Old Reader for most people. In the question“What are the best Feedly alternatives?” The Old Reader is ranked 6th while Prismatic is ranked 9th. The most important reason people chose The Old Reader is:
People from Facebook or Google can be found on The Old Reader so posts can be shared and discussed.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Gesture-based design and intuitive user experience
Prismatic is extremely fast to use and utilizes clever gestures to make it easy to navigate. Apple reportedly sent them a letter saying that it’s Engineers are looking into how they managed to build such a good app.
The app does not utilize tradition navigation bars in order to enable full screen browsing. This makes reading long form content or viewing images a fantastic experience on mobile.
Pro News feed optimization
Although Prismatic has a fantastic design, its biggest differentiator from the competition is its best-in-class algorithms that determine what goes into the news feed.
Prismatic uses G+, Twitter, and Facebook feeds to evaluate what the user is interested in. Sources and lists can then be edited to add or remove certain topics.
This app monitors usage and feedback in order to further evaluate user preferences and fetch the most desirable information.
Pro Excellent content discovery algorithm
Amazing algorithm for discovering new and meaningful content. Uses friend and user similarity and sharing to determine the relevancy of content.
Pro High compatibility
Prismatic is available on desktop, iOS, and Android.
Pro Utilizes user location
Prismatic uses current location in order to find local news. If this feature isn't wanted, it can be turned off.
Pro Social
People from Facebook or Google can be found on The Old Reader so posts can be shared and discussed.
Pro Very similar to the dismissed Google Reader
Ever since Google Reader has ceased to be an option, The Old Reader has grown in popularity.
Pro Great UI
A clean, easy to use interface.
Pro Easy to use
Intuitive, easy to overview service.
Pro OPML import
Allows for easy migration from any service that supports OPML.
Pro Freemium
Free version has a limit of 100 sites, upgrade to unlimited sites costs $25/year. Being freemium is a nice option for those that would like to try the app out without putting down any money first.
Cons
Con Doesn't exist anymore. ADMINS can you please take this down?
<looks up at sky> “TECH SUPPORT!!”
Con Formatting issues
Prismatic tries to reformat articles, and many times this is done unsuccessfully. Users commonly have to deal with overlapping text, missed captions, missing pictures, and other formatting errors.
Con Lacks a built-in RSS feed reader
The only option is as a curated aggregated feed. There is no provided way to supply ones own feeds via OPML for example.

Con Not free/libre
This application is proprietary, and thus cannot be modified, freely distributed, or trusted to be secure. Also, if the developer abandons it again, there will be no way for others to continue to update it.
Con No mobile app
Lacks an official native mobile app, but the mobile version of the site is quite usable and there are apps which support syncing with The Old Reader.
However, users have created many apps for a variety of platforms using The Old Reader API. You can check them out here.

Con Not very customizable
While the sources can be added or removed, the feed cannot be filtered in any other way. Display options are limited as well, leaving the user with the standard view.
