When WhatsApp first came around sending SMS in many places like in Europe was not free. It wasn’t free to send SMS to other people from the same country, and Europeans, especially European Students going to university will typically have friends or contacts with different country codes because they didn’t get a new SIM card for various reasons. It wasn’t free to SMS people in the same country, and it was not free to SMS people from other countries.
WhatsApp changed that, without needing you to sign up for an account somewhere and telling people “my AIM is this” or “my email is that.” You were already giving people your phone number when you met them, and WhatsApp was compatible with that. So it requires no extra steps. Just download the app and go and now you can SMS people for free using the contact information you already have, using the contact information you were most likely to give to people you just met.
That was the appeal.
No it isn't. WhatsApp is a replacement for sms, while other software is (or at least was) always some kind of internet messenger that now also runs on your phone.
It wasn't 11 years ago.
The only thing SMS offered was that the other person didn't need to be running anything. WhatsApp didn't offer that, and also didn't improve on the other messengers of the day.
Essentially, 95% of the reasons WhatsApp was successful were things you glossed over here.
And it still is. Even cheap feature phones often have WhatsApp support.
When Whatsapp started out, it was free only for the first year; after that, they wanted a payment. What this experiment has shown, that people did very short term decision without regards for long term.
I reluctantly installed WhatsApp only after everybody around me started using it, or (the more tech savvy among them who already knew how to "open the internet"), switched away from Facebook to WhatsApp.
Everybody who had a phone also naturally had a phone number, and the phone numbers of their friends were already stored on the phone. Nobody outside the "nerd sphere" had a Gmail account 10 years ago, especially not outside the US.
PS: I don't remember ever paying money to WhatsApp, I think that was a short-lived experiment that didn't work out right before the Facebook acquisition.
Except that this is a feature of every messaging app. It's not really a response to
>> It also has no killer features in comparison to any existing messaging app, nor the defunct MSN.