To download Videos from Facebook Android application:
You can save video using the Facebook application also with little workaround.
Follow the Steps Below

1. Install ES File Explorer, a must have application for your android mobile. The best free file manager with great interface and many powerful features. ( I am not promoting it, its really so feature packed.)
2. Now open any video on Facebook application and click on the drop down arrow for particular post to get options.
DOWNLOAD ES

CLICK HERE TO VIEW THE STEPS WITH PICTURE GUIDE: http://betabaze..com.ng/2016/08/how-to-download-videos-from-facebook.html