How Paywalled Sites Permit Access to Visitors From Social Media Sites and Apps
Isoroku Yamamoto (via Hacker News):
However, subscription-based publications face a problem when users click on a link through Twitter or Facebook on a mobile device. Social media apps implement their own in-app browser, which generally do not retain cookies. Websites that require a user login must request the login every time the app is reopened.
This makes for a cumbersome user experience. Thus, publications like the Wall Street Journal disable login checks when a page request appears to come from Twitter.
It does this by inspecting
HTTPrequest headers. The important headers are Referer and User-Agent.
Previously: Publishers and the Pursuit of the Past.
