Dive Summary:

• Facebook's updated iPhone and iPad apps chose native iOS code for key functions over the HTML5 code that previous incarnations of the apps had been using.
• Facebook's engineering team found speed and feature upgrade issues that were better solved without HTML5, though the current app currently uses both codes for certain functions.
• Todd Krabach, a Facebook software engineer, walks through the decision-making process that his team went through as they made these key decisions.

From the article:

Facebook’s new app for iPhone and iPad has made an impression on users with a significant improvement in speed and performance. In the world of software development, the project has also gotten lots of attention because of the company’s decision to shift key components of the app to native iOS code, moving away from HTML5.

But the engineers working on the project didn’t set out to make any grand statement along those lines. They just wanted to make a better app. ...