>> neither I know personally any other European using it.
>
> Thank you for this information.
> The Italians I just visited *all* use it.
> I don't get why.
>
> They want *me* to use it (to communicate with them), so I installed
> it, but it's only free for a year and then I'll have to either pay
> or get closer friends! :)
>
> But why do the Italians all use it?
> Why not just use SMS?
To understand, you first need to know which kind of phone plans are
offered in Italy: for most people, it is a prepaid fare where for some
money (say 7€) you get a fixed amount of _inland_
phone traffic/sms/traffic data (say 200 minutes/200 sms/1Gb)
You have an vast number of different plans which changes constantly, but
this is the idea.
If you finish your prepaid traffic, then everything becomes quite expansive.
This means that sms can become a real black hole for your prepaid credit.
Given that you don't pay internet traffic (that is: instant messages)
when you are at home (in the sense that probably you have a flat
connection), when you are at work and when you are at a free hotspot
(café, restaurants and so on) and considered that even if you use your 3G
connection instant text messages uses a very small amount of traffic
data, this explains you that on the whole using an instant messaging app
makes you save a lot of money, since instant messaging is the most popular
way of getting in touch.
To this, you must add many advantages of instant messaging apps over sms;
for example:
- messages as long as you please
- multimedia messages
- possibility of using groups
All in all, it is a bit like using emails, but much more immediate and
easy as you just send them like if they where sms.
All this, should explain why an instant messaging app is a killer app in
Italy.
As to why whatsapp over others like telegram for example, there is no
real answer: probably it was the first to get on the scene.
Surely it became vastly widespread. Once everybody you as it, a person
entering the smartphone world is virtually forced to use it to
communicate with others.