First spotted by Claycord, the vehicle is a Dodge Caravan with a four-camera rig mounted on the roof. KPIX reached out to the Department of Motor Vehicles and received confirmation that the vehicle is leased to Apple.
When Claycord asked the driver what the vehicle was for, he "would never give an answer."
There are two possibilities as to what it could be: A Google Street View competitor under development, or a secretive self-driving car project. Analyst Rob Enderle told KPIX that he suspects the latter, saying that it has "too many cameras" to be a Street View-type technology. Apple doesn't have a license to test self-driving cars itself, but according to Enderle, this doesn't rule it out - they could be working in partnership with a company that does.
If so, it'd be the second major entrance into the field in less than a week. Uber has also recently announced it is investing heavily in self-driving car research.
Apple Insider takes a different view, suggesting it's more likely to be a Google Street View competitor. Apple ditched Google Maps for its own proprietary mapping service in 2012. It was initially poorly received due to rampant bugs, but the company has been working to improve it ever since.
Street View remains, however, one of the few killer functions that Apple's offering doesn't have a version of. (Microsoft, meanwhile, has Bing Streetside.) The 12 cameras on the Apple van are also reminiscent of the 15-camera rig seen on the newest Google Street View cars.
A commenter on the r/Apple Reddit community says they drove behind one of the vehicles "in the Far East part of the Bay Area." It suggests that "they are not just doing big cities."
Here's footage of a similar vehicle with California license plates spotted in Brooklyn in September: