Inferring velocity vectors would be very useful for analyzing traffic flows, impacts of lane widening/reducing, signal timing, ML for adaptive traffic management, etc.
None of those things are nefarious and don't necessarily provide additional knowledge, as long as care is taken to fully deanonymize and fuzz start/stop/end locations of trips or associate trips together.
People agree to provide this information to services like Waze etc for exactly these tasks.
Hmmm... I think there are only a handful of nefarious uses for this technology but a plethora of real-world applications. Almost all of the nefarious uses revolve around GPS and individuals. If you take that out, the set of applications is enormous-1.
It’s strange to me that people read something like this and infer the absolute inverse of the actual situation. That is definitely a “thinking fast” reaction.
Would you be interested in giving them your phone number? how about your contacts as well? maybe your own voice? apps have you've installed? and when you're not using the app, keep them posted on your location while you're at it too.
> Them selling my data to others without telling me is unethical.
Ever heard of 'Real Time Bidding?', Google sells your data to advertisers to the highest bidder [0]. Planning on becoming an activist? I've got news for you, law enforcement also want your data and Google sells it to them upon request at any time. [1]
I know they do, but a lot of their users don't which is unethical. But this comment was about the Jet database listing a use case about speed vectors. There is absolutely nothing unethical about that use case nor technology. All the other issues you list, absolutely, but those are not things Jet does.
Unfortunately it is under a company known for shutting down products and that spies on you. It is better to use alternatives like Open Street Map, or if there was absolutely no other option, Apple Maps.
The point is that Jet can track several million distinct keys, even on a single machine, and finding velocity vectors boils down to linear regression sliding window against two FP variables.
If your concern is why you would specifically want to track locations, the answer is that there are plenty location-based apps that track locations with user's consent.
Here are some examples where user consent is undisputed: ride hailing, bicycle rental, street navigation, running/biking/sailing contests, location-sensitive searches. These are the kinds of applications for which Hazelcast Jet offers easy scaling into millions of users.
None of those things are nefarious and don't necessarily provide additional knowledge, as long as care is taken to fully deanonymize and fuzz start/stop/end locations of trips or associate trips together.
People agree to provide this information to services like Waze etc for exactly these tasks.