It did take some persuading. I think the main reason I was able to pull it off was ironically because they're not that technical. I bet most of my friends don't even know what Slack or Discord is. That's not to say they're dumb or anything - they just don't spend as much time online as one would think.

Previously, we were mostly using group texts or Snapchat/Instagram to communicate, so the biggest selling point was the fact that we can share full quality pictures and videos between iOS and Android people.