The Narrow-Band IoT radio protocol seems to have been around for a few years, but I'm struggling to identify any manufacturers of devices that are actually available to buy (either from traditional distribution or developer component suppliers). I've seen plenty of discussions of the protocols and some field-trial roll outs, but nothing that seems quite prime-time.
I found some module like Quectel’s BC95 NB-IoT, SARA‑N2 NB-IoT, Sequans Monarch, FourGee-1160 on the Internet but I could not find those price and supplier.
Should I be looking for anything else similar, or is this technology still in development?