Facebook today launched a major update to its iPhone app, Facebook 3.5, bringing the mobile experience for groups and walls closer to privacy controls, onscreen navigation and UI enjoyed by users of the desktop Web version.

The new Facebook update for mobile now allows you to tag your friends and places in posts, and makes link-sharing much easier.

Facebook is the most popular app in the iTunes App Store with more than 102 million users more than a year ago. This number is sure to have grown considerably in the last year, now that Facebook boasts more than 750 million registered users.

As reported on Mac Stories:

Facebook 3.5 also comes with bug fixes, as mentioned in the changelog:

Improved Notifications speed
Fixed a number of Chat bugs
Made it easier to select filters in News Feed
Fixed a bug with the Notifications bar disappearing
Fixed a number of Photos bugs
Improved performance and stability overall

We recently reported how a secret version of Facebook for iPad was discovered hidden in the current version of iOS, though access has now been blocked.