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Shelby Genius is available today in the iOS App Store! Download it here.

At, we love video and we love new technology. And we’re
dedicated to giving our users new ways to discover and experience
video. Because the right video might inspire the next entrepreneur,
teach a future NHL player how to skate backwards for the first time,
or just make you laugh when you’re feeling down.

Shelby Genius is a brand new type of video search. While traditional
search engines (Google / YouTube, for example) are great at finding
specific information, they’re not always the best way to find new
sources of inspiration or entertainment. We think Shelby Genius is the
first step towards a more fun, fuzzy type of video discovery. It’s
where search meets serendipity.

Instead of a pure textual search of the video title or descriptions,
Shelby Genius is powered by what people like and share across the web.
We’ve been constructing our Shelby Video Graph for quite some time —
it tracks what people are sharing on Facebook, Twitter, Tumblr, etc.
When people share a video out on those social networks and blogs, it’s
a strong signal that the video had some special meaning to that person
— that either they liked it, or it made a strong impression on them
for some reason.

We use this large dataset of signals to do item-based filtering (a
type of collaborative filtering algorithm) to produce video
recommendations. It’s a very similar approach to how
produces their “Customers Who Bought This Item Also Bought…”
recommendations. We also take into account general popularity of video
shares to try to avoid recommending just the most viral videos all the

We wrote a custom item-based filtering implementation in C that’s
optimized for speed and memory efficiency, which allows us to update
the recommendations frequently at a very reasonable cost, and it also
prepares us for incorporating video sharing information from even more

An iOS app seemed like the perfect way to debut Shelby Genius. We all
love using our iPhones to entertain ourselves for a few minutes here
and there, and Shelby Genius on iOS is a great way to find great new
videos to watch during that spare time. Also, if you have an Apple TV,
you can have Shelby Genius continuously play videos to your TV via
AirPlay (even when the app is in the background!), which is great for
parties (music videos) or settling down for an evening of longer

So get out your iPhones and iPods (native iPad version is coming
soon!) and head over to the app store to download Shelby Genius.

And remember to share any great videos you find because you’ll be
contributing to even better, more serendipitous video discovery in the

  1. shelbydev posted this