Back in the 1990s I worked in the field service dispatch center for a medical equipment company. The reps carried pagers and our initial attempt to contact them was by paging. Cellphones were rare then and coverage areas were limited, so the reps relied on a landline somewhere —often a pay phone—to contact us. I worked evenings and I remember one rep, who was on call that night, checking in to say he was headed to Miles City, Montana, about a four-hour drive. He was out of pager range the whole trip and told me he would check in again at the next pay phone—about two hours away.
In the early 90s our office paid an additional fee to send text messages to our pagers. The idea was if you were out in the field and a call came in for service nearby the secretary could just text you the instructions via her desktop.
All she ever typed was, “call the office” so they canned it.