Originally posted by rod_grant so no GPS is a definite then.
Well GPS has not appeared anywhere in the specifications or wireless registrations so far, so I thought that was a given now.
I think the numerous power and connectivity similarities to the GR III are more than coincidental and it will probably work in the same way. With the GR III, you can connect to a smartphone to share GPS data for geotagging via low-power Bluetooth. In this mode, a satellite icon appears on the screen.
This would be frustrating if you had to reconnect every time you power off, but there is a setting where you can select whether the Bluetooth connection is maintained when you power off. Presumably, the camera is not fully powered off when this is set, but in some kind of sleep mode where the connection to the phone is maintained. For the GR III, this is a bit of a dilemma, because the battery life is so limited. But the K-3 III's battery is much bigger, so while it will have some effect, I don't expect it will be so bothersome.
For using Astrotracer no phone connection is going to work, so the accessory will be required. But I don't see this as a big issue, because once you are doing astrophotography, you are lugging around a tripod anyway, so the external unit is tiny by comparison. Also, by separating the body from the GPS unit, there is the possibility of Ricoh making a new, improved GPS module. It might be time for that anyway. My opinion is that astrophotography is more niche than flash photography, so it doesn't need to be built in, especially if it compromises the strength of the body.