In favour of whatsapp:
- You've already got it installed
Against whatsapp:
- It's one of those tech platforms owned by and run for the benefit of evil billionaires
- The source code isn't available, so nobody really knows if it's secure at all
- The metadata probably all just quietly flows into the Facebook data maelstrom
- It never worked properly on my android phone that doesn't have Google services
- It differs from Signal only in ways that make it worse
It was a while ago so they might've fixed it by now, but I remember the problem being that notifications didn't always come through.