Last night, Dave Morin, who manages the platform at Facebook, announced a number of changes to the Facebook Platform. Most are aimed at reducing application spam and making the Facebook experience better for users. The updates include:

• deprecating code that allowed developers to show different UI to profile owners and visitors, as previously reported
• a consolidated application invite process–no more misleading ‘spam your friends’ screens
• eliminating external email through the Facebook API, for now
• new metrics for the Facebook Application directory that focus on engagement

The change to the Application Directory to focus on engagement metrics is the most interesting. Just this morning, Facebook changed the way it counts an application’s user base from total installations to daily active users, where “active” is defined as:

• Going to the canvas page
• Clicking an FBML link
• Mock-Ajax Form Submission
• Click-to-Play Flash

Currently, the “most active” apps (defined by highest percentage of total users that are active) are:

• WarBook – 18,073 daily active users (42%)
• Scrabulous - 157,197 daily active users (37%)
• Hatching Eggs – 106,975 daily active users (35%)
• Are You Interested? – 92,534 daily active users (33%)
• Premier League Picks – 26,631 daily active users (27%)

It’s interesting that the two most active apps on Facebook are games. Most applications, by contrast, have an 8-10% active user rate. More to come.

[tags]facebook, application, metrics, engagement[/tags]