The recent travels of the author’s iPad as collated by iPhone Tracker
There has been much recent concern surrounding the discovery of a file on the iPhone and iPad that keeps a record of everywhere your device has been when operating. The file contains data on latitude and longitude along with a datestamp which denotes the time in seconds since January 1st 2001.
After doing work making data visualizations of radiation levels in Japan Pete Warden and Alisdair Allen turned their attention to mobile devices. This is when they discovered the positional logging file resident in the iPhone.
The existence of the file had been known for some time to various law enforcement investigators. However, Peter and Alisdair felt that the best way to bring the attention of the wider public to the existence of this data record would be by the writing and release of their open source app — iPhone Tracker.
Judging from the amount of discussion taking place on the internet over this matter they have been successful in their intentions.
Gary Delaney CEO of Loc8 Code has over thirty years of experience as a GPS and Electronic Positioning Consultant. The first misconception that he would like to clear up is that the presence of a data log does not mean that your phone is being used as a tracking device.
“From my own experience in the GPS and geo-positioning world tracking has a very specific meaning. It would be a device that would send information to another location, to a server or to a processor of some support which would then be available to a third party.”
For instance, when you switch on your satnav on in the morning to work effectively it needs to know where it is. To help make the process more rapid the device uses the last position and last time taken from a log it keeps.
“This is a track log (which is a different idea to tracking ) which maintains a log on your device of where you have been. That isn’t tracking because tracking implies that information would be sent off to somewhere else where someone else could see it. The information is on your device and it is up to you what you do with it.”
Although the Apple file moves from device to device when syncing and updating there is no evidence as yet that any information is being sent back to the company. Gary suggests that the existence of the file may stem from the initial problems Apple had with signal strength for their iPhones.
“Some developer may have put a file in there to monitor signal and position calculation to try and compare it to normal network coverage in a particular area and identify how much worse they were. That would be a rational perception.”
Also Gary suggests that there is probably no real concern for privacy issues as the data is recorded very inaccurately.
“The data is not GPS data but Cell-ID data and Cell-ID has all kinds of variances in terms of accuracy. It could be 50 metre or a 100 metre accuracy. Outside of urban areas the accuracy could be a kilometre or several kilometres.
“Basically when your phone is powered and operating is constantly sending out a message to the phone networks that says, ‘I’m here, is there anybody listening?’ This is true for any phone not just an iPhone. They are constantly polling. They are constantly saying, ‘I just want to double-check that there is a network available and if someone is looking for me that is here.
“The phone is constantly registering itself on the network and with Cell-ID they know which mast the phone is talking to. They don’t know, necessarily, how close the phone is to the mast. In an urban area it is possible to triangulate your position as masts are closer together.
“In non-urban areas your phone could only be talking to one mast and it becomes very difficult to know how far you are away from it. It is possible to measure by means of signal strength but that can still vary in accuracy from hundreds of metres to kilometres.”
We know that companies like Google would very much like to know as much as possible about our movements. However, you don’t need a specific file sitting on a device to do that.
As Gary points out that our location data is recorded by, “All the carriers. There are agreements as to how this data is handled. The police can access it and do access it. You don’t need a specific file on the iPhone to do this as this information is being recorded by third parties anyway.”
While the reason for the file being present on the file may be innocent one issue still exists in terms of the ease of access to the data. In normal circumstances fairly rigid legal procedures have to be complied with for third parties to access your data from the information that the network carriers have about you.
The existence and relative accessibility of this file means that all a third party really needs to do to obtain details of your travel history is be able to access your phone or other mobile device.
Of course, many people feel there is no issue with others knowing their whereabouts and having access to their location history. Foursquare, Gowalla and Facebook Places wouldn’t exist without the willingness of a substantial number of people to share their geo-location.
However, people using these services also have the option not to share. All that maybe required in this instance to reduce concerns about privacy vulnerability is to have a share or not share option so the device user can have control over the information.