Colin, 2E0XSD, raised an interesting question this afternoon in the Wainwrights On The Air forum when he asked what the rules were regarding making contacts using APRS. I confess that I hadn't thought about it and haven't come to a conclusion at the moment.
For those who think that APRS is merely a way of using ham radio to transmit position reports that can be received and tracked I should explain that it is a lot more than that. One of its best features, if one that is not all that widely used, is the ability to send text messages to other APRS users. For example, if you see someone's position on the map and would like to contact them on the radio you could send them a message to ask whether they are on the air and what frequency and mode they are using.
You could use APRS text messages to exchange exactly the same kind of information with another station that you might exchange in a normal digimode contact - signal report, name, QTH, locator and so on. This could arguably constitute a valid contact. But most of the time APRS users are not in direct radio contact with one another so the messages may be passed with the aid of digipeaters: stations that receive an APRS packet and rebroadcast it. Even more common these days is the use of internet gateways (IGates) that route messages between APRS stations via the internet. There are also an increasing number of APRS users who use mobile devices and the cellular network to send and receive APRS. So I have come to regard APRS as a kind of hybrid system that is not purely amateur radio and I do not regard conversations held using APRS messaging as radio contacts in the sense that I would log them, QSL them or use them to qualify for an operating award.
But that's just me. If two people exchange APRS messages over RF with no digipeaters or IGates involved, is there any reason that this should not count as a contact?
I must confess to having mixed feelings about APRS. When I first found out about it I thought it was an extremely useful system and I still do. My wife Olga worries when I go walking in the hills on my own and likes being able to see where I am at any moment on a map on her computer. If I don't return she will know my last position and could send someone to look for me. And it is a useful way to alert WOTA summit chasers to the fact that you are approaching a summit that you are going to activate. But I quickly became disappointed when I discovered that this functionality could not be achieved if you relied solely on amateur bands RF.
Then I discovered Lynn KJ4ERJ's program APRSISCE which can run on a data enabled mobile phone and connect to the internet-based APRS infrastructure and I was able to get the kind of usage I envisaged from it. (In this part of the world even the cellular data coverage isn't 100% but it is still a big improvement.) But although I now use the mobile client whenever I am on some radio related outdoor activity, I found that using an internet connected client destroyed the radio interest because I could now communicate using APRS with anyone, anywhere with the same kind of reliability as sending an SMS or an email.
APRS is too useful to hobble it by insisting on using only amateur bands RF as the transmission medium. Because of that I don't feel it can be used to make contacts or QSOs in the sense that is generally accepted within the hobby and I'm not convinced that it would be right to make an exception for message exchanges that are "direct." But I'd be interested in other people's opinions on the matter.