Its Google Play listing now reveals it has scored over 100 million installs meaning it's taking the footsteps of the regular messenger app and in no time, it should add more millions to the numbers.

Facebook Messenger Lite app built with an aim to operate with as little resources as possible (especially data and network). I mean the app is targeted at people using low-end devices and those residing in areas with low network.
So in line with the focus, it was made available in a handful of developing countries first, before expanding globally.
In October this year, the app officially arrived in the US, UK, Canada, and Ireland.