This is a really good topic. I wish I knew the answer.
I try to be available in whatever way a resident prefers to communicate. Our phone service is provided by the same company that provides our internet and email (Comcast,) and we can send/receive text messages on our office computer just like a cell phone. Most younger residents prefer email or text, but we still have some residents who don't even have a cell phone or computer.
Most of my residents are on facebook, but few of them follow or contact my community there. I even have a QR code so residents can just scan it on their phone to get to our page. I forward my office phone to my cell when I am not in the office, and I have a drop box so residents can drop things off at the office at their convenience.