There are options sure but on my friends case I can see people aren't so eager to leave the most popular applications/networks, the privacy argument is often shunned with classic "I don't have anything to hide" line and often one is "I won't be installing another app on my x/y/z".
But Telegram still seems to be most popular second choice after Messenger and/or WhatsApp - I've seen recently two people joining it out of sudden (perhaps messenger gained traction because of Belarus situation); personally that's my default instant messenger nowadays, while Signal is the backup one. I'd like to move everyone to element/matrix but that's rather impossible to achieve...
Signal can also function as SMS client on Android, so it's easy to communicate with those who have Signal or use plain SMS; besides additional hardening against SMS based exploits.
In Europe, Whatsapp is ubiquitous. FB Messenger and iMessage are pretty rare here.
Edit: looks like I was wrong. I'm in the Netherlands. In the Netherlands and our neighbouring countries, Whatsapp is ubiquitous, so I presumed the rest of Europe was the same. I guess this proves that assumption is the mother of all failures.
I'd say >50% of smartphone users have Whatsapp in the UK and >50% of smartphone users have FB messenger, of course quite a few have both. I prefer Whatsapp, but contacting a small or large business like a pub or takeaway often works surprisingly well with FB.
@ThePadawan Got it now! WhatsApp did a great job in tricking users with their interface. No other pun intended, but it fits perfectly in the context: "What's the App?"
I remember I missed a few calls from my mom recently, and she asked me if I noticed her missed calls. I didn't have any missed calls as she was calling me through WhatsApp, but in such a way that she thought is the "regular" way of calling. I explained, now she knows. Not sure where this is going...
In India, WhatsApp is the gateway to Internet for millions as many of its users wouldn't have ever opened a browser or received an email.
WhatsApp new version updates gets prime time News spot in even prominent, respected News channel.
Social structures are being built on WhatsApp here, Relatives get offended when you don't join their WhatsApp groups, people don't believe when you say that you don't use WhatsApp, Package disptach details from eCommerce arrive through WhatsApp(no permissions asked) and of course spam arrives through WhatsApp(Local shops wish for your birthday because you signed up for that damn discount card 10 years ago).
A lot more than with SMS. You can send someone an SMS but they are not going to respond because either they cost money or they have some tiny allowance of them.
The point is that the penetration of WhatsApp is way higher than the penetration of unlimited SMS plans. So whatsapp has broader reach.
SMS only works if you live in a region where unlimited SMS plans are standard AND you don't have any friends outside of that region OR WhatsApp doesn't have market share there. Basically only US.
Eh, most messengers use phone number as the primary identifier these days. Whether I use Telegram, Signal or WhatsApp, I add people using their phone number. In the last 3 years or so I can think of one exception where someone preferred Discord but I still got their phone number as a "backup".