Smartphones rule the world. They can do everything but wash my car, which I hear is a new feature of the iphone 5. But there are some things you need to keep in mind when using them, cause they know a lot about you and can reveal a lot of things you wouldn't think about.
Most people have some kind of location based application on their smartphone. Google maps, Google Locator, Foursquare, Loopt, Whrrl or a million other apps. They rely on your GPS coordinates to tell you what is around you, how to get where you are going, and who else might be around. If you are using these kinds of apps and taking pictures with your smartphone, you might be capturing more than a nice sunset or a goofy friend.
What people may not inherently be aware of is that your phone is not only taking that picture, but it may be secretly recording a bunch of other data about the picture in the same file. Things like the time of day, the resolution, etc. are all normal and expected. If your phone has a location based app, it might also be recording the exact location of the photo. If you don't do anything about it, that info is automatically uploaded with the picture, buried in the code, available to anyone who goes looking.
For some pictures, having the location isn't that bad. Remembering where that awesome restaurant is in Thailand can be helpful next time you go back. Sorting through your vacation pics based on locations you visit can be helpful too. But you might be uploading pics that have information you don't want to share.
What if, for example, you uploaded some family photos from Christmas onto Flickr. If you took those photos with your Android phone or even with a GPS enabled digital camera, chances are, the Flickr image you upload from those devices has the GPS coordinates for anyone to see. If you celebrate Christmas at home, this might be a very bad thing. This could be especially troublesome if the pictures show a nice flat screen tv, a pile of ipods and some other cool electronics in the background.
This data allows potential thieves to amass huge databases of people and their addresses and link that information to their Twitter feeds and other social networking sites. As soon as you tweet about dinner in San Fran, a malicious follower will know you are hundreds of miles from your home in San Antonio, and might take advantage.
Stalkers can use this data to hunt their prey. Stalking isn't just a problem for celebrities. It's also a problem for the other 3.4 million people a year who are stalked in the US. That is almost 1 out of every one hundred people. Careless use of your digital devices will only make it easier for stalkers to hunt you, your friends, or your family. Even taking a picture of some ducks in the park with your Blackberry can be a problem.
If a stranger sees you taking that picture, they can search through the various photo sharing sites, not looking for pictures of ducks, but looking for the pictures taken at that location near that time. If you have that geographic information included in the file with your duck pictures, you might also have geographic information about your house, work and other favorite spots secretly buried in your other photos. This lets that city park creep know exactly where you live, even though you have never even seen this guy.
Even a sneaky boss might be suspicious of your sick day taken during playoff season. A search of photos, even if they aren't tagged with the specific event, might reveal that you were nursing a cold one at the ball park instead of nursing a headache on your couch when you called in sick.
First be aware whether your phone, smart phone or regular digital camera records location. You may be able to turn off the GPS location recording on your phone. If not, refrain from posting any photos onto the internet. If you do, use a program to delete that information from the file.
You can delete that data (called EXIF data) from your pictures in photoshop or this free program which I haven't tried out yet.
If you are really serious, you can refrain from ever taking a picture at or near your home. You can also try and get friends not to do that either. Good luck with that one.
The solutions already listed will still not do anything to prevent hackers from stealing your location from your phone service provider. If that idea makes it hard for you to sleep at night, use a prepaid cell phone instead of a nice Blackberry and don't use GPS enabled digital cameras.
Make sure to keep as much control as you need over your digital life. Use good habits when using new technology to prevent unwitting disclosure of valuable personal information. Ensure tools like Spy Bubble are not on your cell phone(s). Use proxy servers to do anonymous browsing, use good privacy software, encrypt files and encrypt emails, and keep your home address private.