Our hospital is looking into something called Spok for secure messaging. Should work whereever the cell phone has wifi or cell service. It's a secure texting app that's HIPAA compliant and has desktop/web versions so that the operators or nurses can send us texts without having to use a phone. Added bonus of read receipts and ping-back to the sender (if wanted) if the message isn't read in a timely manner (ie: STAT pages).
At least that's what our IT guys told me. We haven't gotten it yet.