China plays follow the phone
An exercise in crowd
China is planning to monitor population flow by tracking mobile phones, in the interests of traffic management, though more nefarious motivations do suggest themselves.
The system, which has been announced by the "Beijing Municipal Science and Technology Commission", involves tracking handsets as a proxy for people, in order to spot when areas are becoming congested with people or vehicles, with a view to providing accurate congestion information. The system will first be trialed in northern Beijing Huilongguan, and Tian Tong Yuan in Changping District.
Some people might be concerned about the security implications once the government starts tracking 17 million mobile phones in real time. But the People's Daily explains  that the Commission spokesman "razed out worries about leakage of individual privacy [sic]" and that "all personal data are to protect tightly [sic] and opened data has no relation with individual information". Dodgy translations aside, this would imply that the location data will be anonymous; the Chinese government will be able to see where people are gathering, but not who those people are.
That's just like the systems deployed in UK shopping centres today, which triangulate mobile transmissions to track shoppers around the centre without ever knowing (or caring) who the shopper is. The flow of individuals is valuable, particularly to centres, who want to know about footfall past specific premises and how many different stores a shopper visits.
The Chinese system doesn’t even seem to be using that degree of complexity, with the People's Daily suggesting that cell loading (the number of people connected to a specific cell) should be granular enough. The South China Morning Post, on the other hand, takes that concept and runs with it , talking about tracking of individuals "whether in the bathroom, on the subway or in Tiananmen Square", suggesting the Chinese government fears public gatherings might lead to revolution, and that this can now be prevented "with the help of supercomputers" for some reasons.
That's not to say mobile phones can't be used to track people, but most authorities don't bother until after the fact. In Europe, one's mobile operator stores one's movements over the past year ready to hand over to the authorities on demand. Should the UK police want to know if you attended a particular meeting on a particular night then that information is there for them, and it's hard to imagine China being any different. The question is what degree of judicial oversight is maintained, and if one trusts the authorities to defer to that oversight.
Real-time tracking of the entire population sounds scary, but in reality it's already happening and the Beijing project is probably, genuinely, about spotting traffic jams. The Chinese government don't need any additional projects to monitor dissidents; they're already doing it just like our own government does. ®