If we already have a floating action button (FAB) on our mobile app in the right-hand corner, what's the best way to integrate messenger? Can you design a custom button/messenger?

Hey @louis i, you can absolutely create a custom launcher on our mobile SDKs. Check out the "Create a custom launcher" section in the Configuration part of our SDKs docs here.The link I've shared is for iOS, but it's also possible on Android and Cordova.