Social-networking services seem to be about everything but privacy, especially when you're on the go. They're all about exposure — photo sharing, status updates, wall posts — and some even broadcast users' real-time whereabouts.
It's not surprising, then, that finding the privacy settings for social-networking mobile apps can be even harder than in a desktop Web browser.
"This voluntary disclosure of our personal lives makes a social network what it is," said Catalin Cosoi at Bucharest, Romania-based Bitdefender.
But, explains Andrew Schrage, co-owner of the Chicago-based Money Crashers personal-finance blog, privacy settings on mobile devices are just as important as those on your personal computer.
"Identity theft is on the rise, and scammers are looking for any way possible to steal your personal information," Schrage said.
[6 Steps to Staying Safe on Social Networks ]
"Our smartphones have far more 'interesting' data about us than even our computers do," said Derek Meister, a Cleveland-based "covert agent" with Best Buy's Geek Squad.
Here's how to make sure your privacy is protected when you're on the go.
The first step toward increasing your privacy on social media sites is to adjust your smartphone or tablet's location and camera settings.
"Your smartphone goes with you everywhere, and can track your location," Meister said. "And most apps will also upload your current location."
Unless you're lost, you really don't need your device's location services to be on. Unless you're geocaching or on an archaeological expedition, you don't need the camera to geotag every photo you take.
"The default for the built-in camera on many smartphone platforms is to add your current location to the image file it creates when you take a photo," Meister said. "If you then upload that photo later, it may be possible for people to see where you have been based on the information within that photo, even if the location-based settings within the social network itself have been disabled."
In Android, open the Settings app, then scroll down to Location Services. You'll be given the option of separately turning off Google's location services (which finds you via Wi-Fi hotspots and cellular towers) and GPS satellite data, as well as whether Google can use your location in its own search results (such as using smartphone motion to estimate traffic flow).
To turn off location settings in Android's Camera app, open the app and click on the menu, where there's a simple toggle switch for "Store location."
Apple's iOS Location Services settings (in the Settings app) are even better. There's a master switch that lets you turn everything off, but if you choose to leave it on, there are also individual toggle switches for each app that uses location data, including the Camera app and all installed social-networking apps.
At the bottom of the screen is a link to "System Services," which shows you everything the iOS device's operating system is using location services for, along with the options to turn each one off individually.
On both screens, purple and gray arrows appear next to those iOS apps and features that are using or have recently used location services.
The next task is to set up the privacy on the social media sites or apps themselves.
Long blasted for its complicated, obscure and frequently changing privacy settings, the world's most popular social network has now made its website much easier to use. Editing the new "Timeline" feature has essentially what-you-see-is-what-you-get functionality, and there's a "Control Your Default Privacy" option that applies to all Facebook apps.
Even better, Facebook has standardized its mobile offerings so that the mobile website at m.facebook.com and the iOS and Android apps (and even the one for the dying HP webOS mobile platform) share a single look, feel and functionality.
Click the three horizontal lines in the upper left corner of the screen to view the menu, then scroll down for "Privacy Settings."
You'll be presented with a detailed page that will let you adjust all the settings available on the full-fledged website, except for those applying to the Web-only Timeline feature.
As with the Web page, settings you adjust on the mobile site or in the apps will become the default privacy settings for all Facebook.
Settings for the official Twitter smartphone apps can be accessed by clicking on the "Me" tab on the front page. In Android, it's on the top right; in iOS, the bottom right. Click on "Settings" at the bottom of the next screen.
Unfortunately, you can't do much to adjust your privacy settings on the mobile apps. The Twitter mobile website doesn't offer a lot more.
(Worst of all, there's no way to log out of your Twitter account on a mobile app; more on that in a bit.)
It's best to go to the real Twitter website, where the full privacy menu will let you protect tweets, mandate secure connections, add or delete location information and even flag sensitive (i.e., not safe for work) content that you may tweet out.
Settings you make on the Twitter "mothership" should flow downstream to the dozens of Twitter desktop and mobile third-party client apps, such as TweetDeck, Echofon, Seesmic and so on. Just think of the official mobile Twitter apps as two more "dumb" clients.
The key setting is deciding whether to make your tweets protected — visible only to your followers. That can be especially important if you're looking for a job.
Of all the major social networks, Foursquare may have the best offering of privacy settings on its mobile apps, almost exactly matching what's available on the full-fledged website.
In Android, click on the menu, then "Settings," then "Account Settings," then "Privacy Settings." You can opt out of sharing your phone number, email address and various location details.
In iOS, click on the gears icon in the top left of the screen, then "Account Settings" --> "Privacy Settings" as above.
Both apps also have other settings that let you view the other apps and services you've authorized to use your Foursquare account, including Facebook and Twitter. Even better, they let you revoke those permissions.
Both apps also have robust notification options. For example, if you're out and about and want to check in on Foursquare, but don't want others to see your location, simply select "no" when asked if you want to share the location with friends.
Doing so will put you "off the grid" and keep your location from being published on other social media sites. But it will still allow you to earn "badges" and keep a record of your personal history.
One of the newest and hottest social media sites, Pinterest is a photo-sharing site where users set up theme-based collections for other users to view. If you're going to post photos from your phone to Pinterest, first adjust your camera's privacy settings, as detailed above, before taking any pictures.
Beyond that, you're on your own. Pinterest's privacy settings are slim, even on the full-fledged website, where privacy settings appear on the user's profile page.
The site gives you no way to block users or to set up a private board, though it does let you block "pins" from appearing in Google searches or on your Facebook timeline.
The single mobile app, for iOS (there is no Android app yet), does not let you adjust settings at all. The "Profile" tab on the bottom right of the app's screen shows a button marked "Account," but clicking on that gives you only the options of logging out, installing a bookmark or giving Pinterest feedback.
The business-networking service was slow to come around to allowing users to set up privacy settings on a Web browser.
It's still difficult to even find the "Settings" link on the LinkedIn website; you have to hover your mouse over your name, but the privacy controls on the "Profile" and "Account" tabs allow for a decent range of options. (Be sure to uncheck "LinkedIn may use my name and photo in social advertising" in "Account" if you've got a problem with that practice .)
Unfortunately, neither the iOS LinkedIn app nor its Android counterpart offers privacy settings of any kind.
In both apps, the "You" tab on the front page will take you to a page with a gear icon in the upper right, which takes you to a "Settings" page. But when you click on "Privacy," all you get is a copy of the LinkedIn end-user license agreement (EULA). The Settings pages will let you log out, however.
Clearly, the only way to adjust privacy settings is through a full-fledged Web browser. It appears that LinkedIn, like Facebook and Twitter, will carry privacy settings across devices.
Google's answer to Facebook may have the strongest and simplest privacy settings of the popular social media services. To find them on the website, you have to click on your profile picture, but once you do there's a dedicated button for privacy settings.
Google+'s clean interface lets you click on the section of your profile you want to edit, and you can control the visibility of each and every posting you make. Best of all, Google Dashboard lets you see exactly what you're divulging about yourself across the Googleverse of Gmail, YouTube, Picasa, Blogger and even Android phones.
The Settings menus in the mobile apps do let you adjust notifications, both those you send out and those you receive, but they're nothing like the paranoid heaven you get on the Google+ website.
So as with LinkedIn and Twitter, you'll be best off tweaking your settings on the full-fledged browser, then trusting the service to apply those settings to the mobile interface.
Finally, the most important privacy setting of all is to remember to log off. When you are no longer using the social media service, whether on a computer or on a mobile device, always sign out of it.
This is where Twitter utterly fails. There is no way to log out of your Twitter account from either the Android or iOS official Twitter apps. The only way to do it is to completely delete the Twitter app.
"If you don't protect your privacy, using a social media site such as Foursquare can allow nearly anyone to discover a variety of personal information about you , as well as where you are located or planning to be," said Schrage. "It is highly advisable to invest the time to keep your personal information private."
Your mobile device is at much higher risk for theft than your computer at home. As more and more businesses trend toward social media, and as that becomes a bigger and bigger factor for prospective employers and your public image, you need to make mobile privacy a top priority.