Developers won't move around most of the time, but they might do so occasionally. For example, a developer might work from a train while commuting. They might even do so intentionally, taking advantage of their daily commute to test geolocation changes in their app.

So it'd be useful to keep the current geolocation updated, although it isn't essential. We can either tackle it here or in a followup change. Either way, I expect that it's fairly straightforward to implement.

Currently, prosthesis sends a request to which the addon then sends a single response after getting the position via *nsIDOMGeoGeolocation.getCurrentPosition()*. To keep the current location up-to-date, we just have to make the addon register a listener via *nsIDOMGeoGeolocation.watchPosition()* and then send a response every time it receives an update.