Facebook messenger is a social networking messenger.It is a mobile tool that allows users to instantly send chet massages to friend on Facebook messenger are received on mobile phone.It is available for android, iPhone, blackberry, windows.It’s only not working massage can be used without voice call and video call but only make all call with this app user but this call not available for window’s phone Facebook messenger app.this app use very easy.this app use offline massage in sim.By the way this app is so nice features.all love people is massaging app.