Facebook Messenger is enjoying a momentous ride to the top of the Android App store, now that Facebook is removing all chat services from its main app, Facebook. It is #2 in the Android Play Store and #6 in the App Store.
Chatting in Facebook Messenger may be cleaner, easier, but users will now have to download both apps if they are to keep using the full service. By keeping the services separate, Facebook can keep it leaner, but no doubt the company will bloat it with advertising or in-app purchase options.
This change will not be affecting all phones – older Android devices, windows phones and tablets, and if you want to keep one app for Facebook, you can look into its Paper app.