>>>>> I naively thought that cellphones behaved in a manner similar to computers (I looked at them as miniature computers) and so just as computers can pick up e-mails in a delayed fashion, I thought cellphones could get caller information also in a delayed fashion, for missed calls, even if the phone was turned off (as computers can). <<<<<

That's not such a naive thought at all. Today's digital cell phones and the infrastructure that supports them are 99% computer-like hardware, whose behaviour can be defined by software. I think that the fact you don't/can't get a list of calls that were missed while your phone was off was just an arbitrary design decision made by the engineers/programmers some time in the past. It would not be difficult for the system to log calls that were attempted to your phone while it was off, and then send that list to your phone when you turn it on.

I generally agree with the thoughts

>> I naively thought that cellphones behaved in a manner similar to computers
… I think that the fact you don't/can't get a list of calls that were missed while your phone was off was just an arbitrary design decision made by the engineers/programmers some time in the past. It would not be difficult for the system to log calls that were attempted to your phone while it was off, and then send that list to your phone when you turn it on. <
Thanks Walter. I agree that this sort of thing should be fairly easy to set up and not too expensive to implement.

I suggest that in fact the technology to send the text message when your phone returns to the system that is available in the Rogers Call Manager might have been more expensive to set up than some form of "off line logging" that would just alert the phone,

However the Call Manager System had the advantage (to Rogers) of being much easier to control for billing purposes. Not much that makes it into the cell phone interface isn't set up so that it can be added as a billable option — or at least an add on option to entice you to buy the product or service.
The decisions about what gets installed on a handset and/or programmed into the system is not about technological possibility — it is about bill add on possibility. The decisions about what gets enabled are made by the marketing departments, not the engineering and/or programming departments.

Smartphones are small computers. If the industry were run by those on the tech side rather than those on the marketing side, we would see lots of things that would be easy to implement in the phones. Because the industry is driven by hopes of financial gain, (some would word that as "greed") we see slow implementation of technology at ridiculous prices. The fact that there is a "market" for Unlocking, Jailbreaking, Rooting, Etc. phones says clearly that the full potential of the phones is being limited by the manufacturers — usually at the request of the carriers. Apple is even more restrictive than the carriers — and those restrictions are to make money for Apple.

The price of cell phone service in Canada is driven by what the market will bear, not the cost of providing that service. There are bits of competition, but those are few and far between.