Why Path limits you to 150 friends

Do you want to see the most relevant stories from all your friends, or all stories from just your best friends? That’s the fundamental difference between what Facebook will show you in your news feed, versus the information shared on Path.
In an interview at South by Southwest, Path CEO Dave Morin told me that the mobile social network doesn’t ever want to use algorithms to change the stories that appear in your feed. Instead, the app is all about telling a story of what’s happening with your friends in a chronological order. That said, Morin expects that there will soon be an explosion in the amount of personal information that users share.
It’s not just things that users self-select to share, like photos — which now make up about 30 percent of all messages shared through the app — or the music that they’re listening to at any given time. Path launched an API with the version 2.1 of its app, with Nike as the first partner to take advantage of it. Through the API, the Nike Fuel Band will share users’ information with the app, keeping track of movement in real-time and even allowing your friends to cheer you on as you run.
In our discussion, Morin hinted that more quantified self-type applications may come to Path, in turn bringing more personal data online. The key to ensuring the signal is high, Morin believes, is to limit the number of friends someone can actually have on the service.
Unlike Facebook, which lets you friend what feels like a near-infinite number of people, Path is purposely limiting how many people you can connect to. When Path first launched, that meant you were limited to 50 friends on the service. Now, that limit has been increased to 150, which is a value associated roughly with the maximum number of people we can maintain stable social relationships with at any given time, according to British anthropologist Robin Dunbar.
“We want to connect you to the right 150 people,” Morin told me. Once you sign up, it uses information from your existing social graph to attempt to highlight those people with whom you’re most likely to want to share that personal data with. It also means not letting you friend people willy-nilly. Once you’ve reached your limit, you have to delete someone before adding someone else.
Importantly, Morin acknowledges that it won’t be the same 150 people that you choose to share with throughout the lifetime of the app. Like real life, some friends might fall out of favor, while new ones will enter your social sphere.