Posted on Apr 10 2011 in Technology Q&A by
Q. I saw a Fox News report that my activities can be tracked via my cellphone pictures. It really bothers me that someone could be stalking my kids using their pictures. What can I do about it?
A. If you have an Android, Palm, BlackBerry, or iPhone, any tracking using pictures (see the Fox News report for details) can be easily stopped. Here’s how!
How It’s Done
Every camera today has data that’s embedded into the picture called EXIF data. EXIF stands for EXchangeable Information File format. This data can range from the model of the camera and what kind of lighting conditions existed when the picture was taken to much more advanced features like aperture, shutter speed, and the location that picture was taken. It’s this EXIF data that is causing concern on cellphones.
How To Protect Yourself
When I watched the Fox video, I had some initial concern, but that concern quickly turned to calm as I realized neither I nor my family members were in any danger. Here’s why….
Two of the biggest potential threats are sharing pictures on Facebook and Twitter. A couple of weeks ago, we talked about ensuring your privacy on Facebook. There’s the added protection that Facebook–and Flickr for that matter–strip EXIF data from pictures. That means even if someone did gain access to the pictures posted to your Facebook and Flickr accounts, the only way they’d be able to determine where the pictures were taken is if you purposefully added that information.
What about Twitter? Well, that’s a bit different. Twitter uses a couple of photo-posting services like TwitPic and yfrog. These both have the capability to “broadcast” the location of the picture, as does the tweet itself. This is easily mitigated by ensuring that if you are going to post the picture, the picture was taken somewhere in a fairly public area like a shopping center or tourist attraction. I happen to use Instagram, which allows me to choose whether or not the location of the picture is added.
This leaves pictures sent via e-mail. That’s a slightly trickier matter. If you think Grandma is going to forward your picture to her best friends, and they’ll be forwarding, etc., it may be time for…
If you want to be conservative and disallow any kind of EXIF data to be applied to you pictures, you can make those changes through the settings on your BlackBerry, Android, Palm, and iPhone. This will ensure you keep location services from adding geolocation info from your cellphone to your pictures. Click here to find out how for your phone. After you’ve made the changes, you can rest assured the only way someone is going to know where that picture was taken is if you tell them!
If you ever have any technology-related questions, please feel free to send them to tech@HEAV.org. We’d love to hear from you!