So the short story is that we're using geofencing to download news content in the background when you leave your preset "Home" location. Super useful for subway commuters. Kudos to @tolar, iOS developer and subway rider extraordinaire for coming up with it and building it in a weekend.
I'm guessing this, like other geofencing activities, is heavy on battery? Does it only trigger once a day (in the morning or whatever) and then stop checking your location?
and here's the smarter answer from @tolar: Geofencing typically relies on cell tower changes, a coarser measure of location than GPS, but one that saves on battery life.