It is a great concept which is nowadays trending in all over world. Everyone uses it like daily for personal as well as professional work.
If you got any trouble then you can contact their support section and get your issue solved easily.
It is very User Friendly and is very usefull for us.
I think their service & support needs to be improved but your issue can get solved now also.
Whatsapp is reliable & is very satisfactory which also improves with giving updates ocassionally.
App has nice and useful features for use which are value for money.