If you're having problem setting up the most up to date version of the Facebook for Android app, you are in the best location.
Facebook Won't Update
While trying to install Facebook using Google Play store, you can review sometimes this error message:
Can't install app. "Facebook" can not be installed. Attempt once again, and if the trouble continues, get help troubleshooting. (Error code:- 504).
The error code 504, is not a concern with the Facebook application, as well as not a generalised Play Store concern. To solve the trouble, try these fixing pointers:
* Setups > Applications > All > Google Play Store, Clear information and Clear cache
* Settings > Apps > All > Google Play Services > Manage space, Clear all information as well as Clear cache
* Restart your phone
* Try to update or install Facebook again.