Reading 2011: The Year the Check-in Died on ReadWriteWeb. Not too sure what to think of it. Of the people I know, only two people who live in the same city as I am have used any of the check-in services I've dealt with, and for neither was it often enough for the serendipity thing ("Hey! You're at the mall, too? How are you doing?!") to happen. I have yet to find another person who wants to share their lat and long via Google Latitude with me. And, I must admit, there's only a small set of people who I'd do that with.
The author lists four reasons why people check in to places — Finding people near you, Rewards, Remembering things and Personal Branding — then proceeds to explain why this is trivial and not lasting and nothing to base much on. There's just not much in it for people to tell others where they are.
But I want to know where I am. Or, rather, I want my desktop, home of my alerting crontabs, to know that I'm near my work, where it knows to alert me like this, or near my home, where it knows to alert me like that, or somewhere else, where it can alert me with a whiffleball bat. Or something. I don't need my friends to know where I am. I don't really want to tell advertisers or employers where I am. But it would be a great boon to me if I could tell where I am. Screen-based alerts are useless if nobody is at the screen.
Be aware that Xerox PARC, the Palo Alto Research Center for the Xerox Corporation, invented computing as we know it. One of the things they had were badges that could tell where you were in the facility, so if someone called for you, the telephone nearest to you would ring, no matter where. That's great and all, but today, everyone has their phone on their hip, so standard wired phones are more and more useless and less and less used.
When I used to work for the medical clinic, I tested badges that could unlock a computer when you got close, and unlock it when I walked away. It seems like it would be easy to write authentication modules that would allow the same thing with Bluetooth, but I'd rather have GPS rolling than Bluetooth most of the time.
There's a Latitude API, but I haven't done more than poke at it. But I suspect this sort of thing will be the real use of location-based computing.