Good to see that Apple has now released a software update (iOS 4.3.3) that means that iPhones will no longer retain information about where they have been!
As Apple, states:
“This update contains changes to the iOS crowd-sourced location database cache including:
- Reduces the size of the cache
- No longer backs the cache up to iTunes
- Deletes the cache entirely when Location Services is turned off”
In effect, this means that the amount of information kept on the ‘phone is limited to a week’s usage, and the location data are no longer backed up on users’ computers.
In response to criticisms over iPhone location data being stored on the ‘phones and backed up on users’ computers, Apple claimed that iPhones were not actually logging locations – “Rather, it’s maintaining a database of Wi-Fi hotspots and cell towers around your current location, some of which may be located more than one hundred miles away from your iPhone, to help your iPhone rapidly and accurately calculate its location when requested. Calculating a phone’s location using just GPS satellite data can take up to several minutes. iPhone can reduce this time to just a few seconds by using Wi-Fi hotspot and cell tower data to quickly find GPS satellites, and even triangulate its location using just Wi-Fi hotspot and cell tower data when GPS is not available (such as indoors or in basements). These calculations are performed live on the iPhone using a crowd-sourced database of Wi-Fi hotspot and cell tower data that is generated by tens of millions of iPhones sending the geo-tagged locations of nearby Wi-Fi hotspots and cell towers in an anonymous and encrypted form to Apple”.
Apple went on to say that the fact that up to a year’s data was stored was the result of a bug: “The reason the iPhone stores so much data is a bug we uncovered and plan to fix shortly (see Software Update section below). We don’t think the iPhone needs to store more than seven days of this data”. Further, their statement also emphasised that Apple believe that personal information security and privacy and important: “Yes, we strongly do. For example, iPhone was the first to ask users to give their permission for each and every app that wanted to use location. Apple will continue to be one of the leaders in strengthening personal information security and privacy”.
For further comment, see:
I wonder how many iPhone users are aware that their movements are automatically being logged in a small, easily accessible application on their ‘phones? Recent, important work by Alasdair Allen and Pete Warden has shown just how easy it would be for unscrupulous people to access this information. It also raises worrying questions about why Apple has done this, and why they have not clearly informed users that this information is so readily available?
Allen and Warden have written a neat Open Source application that enables users to visualise this information – down to a very high level of detail in space-time – called iPhoneTracker. Essentially, Apple stores this information on the ‘phone in terms of latitude, longitude and time stamp. The database of locations is stored on the iPhone, but is also on any backups that might have been made when synced with iTunes.
As Apple and Warden comment with respect to why Apple has done this, “It’s unclear. One guess might be that they have new features in mind that require a history of your location, but that’s pure speculation. The fact that it’s transferred across devices when you restore or migrate is evidence the data-gathering isn’t accidental.”
They also point to the very serious moral and ethical issues that this raises: “The most immediate problem is that this data is stored in an easily-readable form on your machine. Any other program you run or user with access to your machine can look through it. The more fundamental problem is that Apple are collecting this information at all. Cell-phone providers collect similar data almost inevitably as part of their operations, but it’s kept behind their firewall. It normally requires a court order to gain access to it, whereas this is available to anyone who can get their hands on your phone or computer. By passively logging your location without your permission, Apple have made it possible for anyone from a jealous spouse to a private investigator to get a detailed picture of your movements”.
The screen grab from their visualiser shows where I have been using my iPhone in recent months. Perhaps colleagues who have been sceptical about why I have various different ‘phones and different SIM cards will now understand the reason!
We should all be immensely grateful to Alasdair Allen and Pete Warden for bringing this to our attention!
See also Jacqui Cheng’s recent article on this.