You may now sign up for Facebook Messenger without even have a Facebook account. It’s will register your phone number instead just like how others social messenger like WhatsApp, WeChat and etc. All you need to provide is your first name, last name, phone number and optional photo to get started.
It will have all features available in in Facebook Messenger including photos and video sharing, group chats, voice and video calls, stickers and lot more.
Currently the feature is only available in the US, Canada, Peru and Venezuela.