Apple and NewtonOS supported a variety of different mobile networks (eg. ARDIS/DataTAC and CDPD) in the time before the Internet and TCP/IP became dominant. Bu

Apple and NewtonOS supported a variety of different mobile networks (eg. ARDIS/DataTAC and CDPD) in the time before the Internet and TCP/IP became dominant. But it's fair to say that the OS was not built with networking in mind. Later releases of NewtonOS included a TCP/IP stack that worked with dialup PPP (over PSTN modems), wired Ethernet, and early releases of what became WiFi (at that time, WaveLAN). The devices' IR "beaming" hardware meant that NewtonOS had an inbox/outbox concept that allowed users to exchange email, documents, software, etc. This was adapted to work with always-on Internet connectivity, but it was clearly a retrofit (much like MacOS and Windows at the same time).