WhatsApp is the leading insta messasing service
I use this this for its fast performance even slow networks.whtasapp is very use too communication with our family friends etc.a almost everyone at some point of time will send not only picture and video but also document files.t o someone that is far away by using this app.its just simple to do that.b before WhatsApp there was MMS services provide by the network service.but it was never simple and it was expensive.f feature is great one.u can send voice record, WhatsApp calling.i am happy to see my privacy even after Facebook bought the company .it still misses some features which I would have loved to see like stivkres.the emoji have improve now with better organation.
Overall I would say it is default IM service I use everyday of may life