https://www.theverge.com/2018/3/15/17126022/facebook-lite-rolling-out-developed-countries-united-states

Facebook Lite, a version of Facebook made for developing countries that is designed to run on 2G networks, is rolling out to more countries, including developed ones, according to Reuters. Like Messenger Lite, the thought is that people with older Android devices or slower internet connections would benefit from the stripped-down app.

Launched in 2015, Facebook Lite was first tested in Bangladesh, Nepal, Nigeria, South Africa, Sudan, Sri Lanka, Vietnam, and Zimbabwe, but is now available in over 100 countries. It’s lightweight at only 252 kilobytes, and it’s based on the Snaptu version of Facebook that runs on feature phones, but with functionality like push notifications and camera integration. In the forthcoming rollout, the app available in countries including the US, Canada, Australia, UK, France, Germany, Ireland, and New Zealand.