Yes, it actually is that difficult to program. To scale to WhatsApp's level, you can't just base all your message-delivery off a Kafka cluster and be done with it. Amazon Chime still hasn't been deployed outside of us-east-1 and seems nowhere close to a global deployment.
The engineering effort to provide low-latency communications, at geographic and user scale, is very much non-trivial.
People use Whatsapp because that's what everyone else uses. I would prefer Signal but no one I know uses it.
Everyone I know uses Whatsapp.
So I use Whatsapp.
Nobody I know uses WhatsApp. So I don’t use WhatsApp.
See how that works?
The anecdote is supposed to show why one can't just write their own app. It doesn't work that way.
Consider that you're a distant outlier.
You just naturally remember, like you would remember where your friends live. I guess if you are constantly dealing with "contacts" rather then friends it would get confusing.
I use
1. WeChat
2. WhatsApp
3. Threema
4. Frozenchat, a Jabber client with OTR support
Don't have signal yet.
Ah, and I can "chat" via Text message too :-)
2. global leader right now
3. as compromised as whatsapp,has data compliance with multiple countries
4. no name fork of a no name
2. correct
3. Multiple countries? You would need a court order from Switzerland. I am not even sure they can access your messages if they wanted to.
4. Irrelevant because it is a client to an open protocol. Which client you use does not matter. I just named mine.
And even my mother has installed Threema on her phone because a friend of her asked for it. This tells you something. It is hard to come up with another social network like facebook. But a chatting client on the phone? The tide can change very fast there.
Threema gets used more in Europe than in the states. But even a US buddy recently suggested we switch to threema. It is closed source but claims to offer more privacy.
https://threema.ch/en