This is really useful. I am trying to do the same thing (if Shepherd ever gets properly released and workable then I'll be able to use that instead, but not holding out much hope).

But I don't want to poll dbus every few second/minute or two to find out if its changed; using the location api lib means maybe an online lookup for assisted cell-id-location or use of gps. I don't care about keeping the location of certain cell's cached, 'cos I'm happy to manually associate my regular few (work, home basically) with the right code to run my actions I want at certain times.

Do you know what the signal emitted is every time the cell id changes, if there is one - or a more trigger-based action rather than polling it if there's an alternative to dbus?

Or alternatively, am I being too dismissive of the location api (I only briefly skimmed some of the wiki info on it)? Is it possible to use it without relying on cached cell id locations that might fail if cache expires/cannot be downloaded/could return just somewhere in the middle of the country if it only knows I'm in the UK, for instance?