Android 2.1 was released in 2010. The official Facebook app stopped supporting this version many years ago. You cannot download the modern Facebook app from the Google Play Store on this device.
To use Facebook on this system, you need an of the app—specifically a version released around 2011 or 2012. download facebook app for android 2.1
Because the official Google Play Store no longer supports Android 2.1, you will need to "sideload" an from a reputable third-party archive. Facebook 1.9.1 (Legacy Version) Android 2
: Before installing, you must go to your phone's Settings > Applications and check the box for "Unknown Sources" to allow installations from outside the Play Store. 2. Best Alternative: Facebook Lite or Mobile Web download facebook app for android 2.1