Every time you open Signal this week, more and more of your contacts have joined. People are freaking out about Whatsapp sharing peoples data with Facebook. Smart people seem to think it's a real problem, so maybe the switch to Signal will actually happen.
A very active group chat I'm in made the switch to Signal today (from Whatsapp) and it's clear that Signal are a ways behind Whatapp with their interaction design. The whole thing feels slower. iMessage, Whatsapp, Messenger, and even IG chat, feel faster.
Signal also feels, blah. Empty of personality. I don't think it needs much, but something so I don't feel like I'm texting people from a Microsoft product. There isn't a hell-of-a-lot you can do with a messaging interface, but it would be nice to see some small details that made you feel like it was created by people.
Privacy is the driving force behind this wave of switching, I wonder if the UX will be the thing that keeps us there.