
Users are reporting that their Facebook app on Android is now loading links to web sites in an internal browser rather than launching one of the external browsers a user may have installed on their device. There is no indication in the Play store entry for the Facebook app that an internal browser has been added as an update which suggests this may be a beta feature that only a subset of users are receiving. Rolling out changes to only some users for beta testing is a standard practice for Facebook on the normal web interface and seems to be used more frequently with their Android app.
The new internal browser does provide users with a few options via a menu button. Users can share the link, which will open a new post in the Facebook app. They can also copy the link to the article which could be handy for sharing via other platforms. An “Open with…” option brings up Android's intents dialog so a user can pick a different browser or app. Finally, a “Save Link” option is available that will log the site into a user's activity log and mark it as private.
Have you received the update and find it useful or would you rather just jump over to your normal browser?

source: Android Police
I got the beta, it took be by surprise honestly. I wasn’t expecting Facebook to enter the browser world. If you use Facebook for link clicking, it could be useful. Ill have to see if the Facebook browser is caching the pages – it could make the app more bulky than it already is.