Sending & Receiving SMS via WiFi Is there a way to send and receive SMS when a cellular signal is not available, but WiFi is?  I'm often on-site at locations where the building has a strong WiFi (Internet) connection, but a simple cell signal is spotty at best.
SMS is tied in with GSM telephony standard, so the answer to your question is No. 

But what you can do, is use Viber, Whatsapp to send something similar to SMS (not the GSM variety!) to each party provided they have the appropriate app installed.