Whatsapp messenger is the best messenger app for me
If you have number you can start chat, video calls, send your location and pictures and also documents.
You can connect to peoples who are residing in other country too
Only thing is you just to have their numberzs
It also can run in 2G . So you need not recharge 3g or4g
You can also have group chat
Whatsapp is safe and secured guys
I just love it because of speed and daily updates