Now there’s a way to upload photos that are already labeled with their exact latitude and longitude using geotagging, the fancy name for labeling data with information on its geographic origin. Photos with “geotags” have coordinates embedded invisibly in them. Some programs or online photo services use these tags to generate maps showing just where each photo was taken, or to label or organize the images. Not long ago, this capability was mostly done through manual labeling or with costly equipment.

The $129 Eye-Fi Explore Card from Eye-Fi Inc. gives people the ability to wirelessly send geotagged photos from a digital camera.

This week, I tested the $129 Eye-Fi Explore Card (EyeFi.com), a special two-gigabyte memory card from Eye-Fi Inc. that adds a photo geotagging feature to Eye-Fi’s original functionality: the automatic wireless uploading of photos, straight from a digital camera to a home computer or photo-sharing service. If all goes well, users can capture and upload what are essentially geographically prelabeled batches of digital photos — with minimal effort and time.

But after days of testing, I found myself more frustrated as I used this wireless memory card in various places and situations, and found the tagging to be unreliable in one scenario. (Eye-Fi Inc. said my experiences weren’t typical.) At home in Washington, D.C., and while on a business trip to California, I tried it using a two-year-old Kodak digital camera and two different Vista laptops, though it also works on Macs.

Eye-Fi introduced the Explore Card as a follow-up to the company’s original wireless memory card, which it introduced last fall. Once set up, the first Eye-Fi card initiated the transferring of photos to a computer or Web site whenever the digital camera was turned on and as long as it was near a pre-associated wireless network.

Through a partnership with Skyhook Wireless, the Explore card can automatically label photos with their latitude and longitude using data from the Skyhook’s Wi-Fi positioning system. As long as a photo is captured within the Skyhook coverage area, which the company says covers 70% of North America, and the geotagging is enabled, each photo will be coded with data identifying where it was captured.

The Explore Card turned otherwise normal photo-sharing sites into mini maps showing where I had traveled while on a business trip in Silicon Valley. I set my account up to work with Flickr, Kodak Gallery, Snapfish, Shutterfly and Picasa Web Albums, though only one will work at a time. Flickr, Picasa Web Albums and Smugmug make use of geotagged photos by tagging shots with their location data, such as “Downtown Palo Alto, California.” I used Flickr and Picasa Web Albums to instantaneously generate a map showing where I was when I took photos.

On Flickr, each image was represented by a pink dot associated with one of several photos displayed in a horizontal bar below the map. This map can be searched for specific tags (photo labels) or locations and can be narrowed to show images from everyone who uses Flickr, just your own photostream, or only photos from friends or contacts. My searches returned results in seconds, finding shots that were geotagged with “Palo Alto” and tagged by me as containing flowers. I enjoyed looking at other Flickr users’ photos when I searched everyone’s images, specifically in cities where I recognized landmarks.

Picasa Web Albums showed each geotagged image on a map by placing tiny versions of each photo on the map. In certain cases, when I had multiple photos taken at the same spot, photos appeared with lines drawn from them to a spot, much like spokes of a wheel. I also looked at my Picasa photos on maps in Google Earth; a quick link to the program is conveniently found at the top of the Picasa Web Albums screen.

Another key feature of the Explore Card is its hotspot connectivity. The card is capable of working in any Wayport location, which includes McDonald’s (MCD) restaurants and certain airports and hotels. Though using Wayport locations normally requires sign-ins and/or payment via a computer screen, the Explore Card works as soon as the camera is turned on in these locations. This service is free for the first year, but after that, it costs $19 annually to continue.

Finally, the Explore Card notifies users via SMS or email messages when photos have either started or finished uploading; or if these uploads are interrupted, which happened to me a few times. This is useful in Wayport wireless zones, where the camera has no real way of signaling when an upload is finished or when a computer isn’t handy.

In a hotel with a flaky Wi-Fi network, the Explore Card was crippled, though I blame the hotel for this inconvenience. But even when I traveled to a local McDonald’s, where Eye-Fi’s maker has a deal for free Wi-Fi for its cards, the Eye-Fi stuttered and couldn’t consistently upload photos. When I plugged the card directly into my laptops, the results weren’t much better.

If you aren’t within Wi-Fi range while taking a photo, it won’t be geotagged. I ran into this issue in one instance: On California’s highway 101, I took a handful of photos, but when I checked my Eye-Fi account later, none of these photos was automatically geotagged.

Some people worry about privacy settings when it comes to uploading geotagged photos directly to a sharing Web site. Settings within the Eye-Fi Manager make it easy to adjust permissions to determine who can see your photos within each of about 25 sharing sites.

Users can opt to share photos only to a home computer through their own Wi-Fi network, and a special card is designed for just that: the $79 Eye-Fi Home. This is meant to serve as a shortcut for transfers.

The original Eye-Fi, which costs $99, was a useful tool as a wireless memory card, but I didn’t have as much luck with the more expensive Eye-Fi Explore. Still, when it did work, I found geotagging to be a great way of automatically labeling and organizing my photos. Instead of just being neatly stored in a folder on your computer, geotagged images are given a spark of life and relevancy when plotted out on a map.

Edited by Walter S. Mossberg

Email: mossbergsolution@wsj.com

Trying to share information with people on your Web-based networks can introduce another layer of digital jujitsu. It can be awkward to snag a photo or a snippet of text from one Web site and send it to a friend in a social network on another, or post it to your own blog.

But I’ve been testing a little-known Web browser that attempts to solve these problems. It’s called Flock, and it bills itself as “the social Web browser.” I found that it worked well, but it isn’t for everyone, and it has some important downsides.

Flock is a modified version of the excellent Firefox Web browser that tacks on some special features for social networkers and bloggers. It’s available free at flock.com in essentially identical versions for Windows, Mac and Linux.

Flock adds a special vertical “sidebar” at the left of the browser that keeps your social networks, photo sites or news feeds visible at all times, regardless of what page you’re viewing in the main browser window.

For instance, with Flock, you can see that you have a new friend request in Facebook, or that a pal has posted new photos in Flickr, without clicking away from reading this column in the main browser window.

But, wait: There’s more. With one click, you can display a horizontal “media bar” across the top of the browser containing thumbnails of all of a friend’s photos or videos from a social-networking or photo site, again without changing what’s in the main browser window.

These two special bars also allow you to take action. For instance, you can just drag images and text from Web pages into the sidebar to share them with friends listed there. And any photo on the media bar can be quickly emailed or posted to a blog.

There’s also a “Web clipboard,” which can save any text, image or link from a site in the main window by merely dragging it to the Flock sidebar. Once an item is in this clipboard, it stays there until you delete it.

Flock has its own built-in blog editor, which allows you to quickly compose, edit and publish blog posts containing interesting items you encounter on the Web. And it creates a special personal Web page, called My World, which combines your social-networking updates, news feeds and photos.

I found Flock productive and fun to use. I tested its special sidebar with my Facebook, Flickr, Picasa and YouTube accounts, and with my favorite news feeds. I also used another of Flock’s features, which let me check my Gmail and Yahoo Web-mail accounts without navigating to their main pages. And I published several posts from within Flock to a test blog I maintain. All of this worked as promised.

In my tests, I used the latest edition of Flock, version 2.0, which is built on the new Firefox 3.0 browser. Even though this latest iteration of Flock is still in beta status, I found it to be quite stable.

But Flock isn’t for everyone, and it has some significant drawbacks. For one thing, you’d need a fairly large or high-resolution monitor to accommodate the Flock sidebar and media bar without reducing the size of the main browser window so much as to require too much scrolling. Even with a big or high-res screen, you will see fewer toolbar links and browser tabs than normally.

And, Flock has a busy, even frenetic, look that can be distracting and annoying. So many things are going on at once that it can be hard to concentrate on the main attraction: the Web page you are reading in the main window.

Also, while Flock does indeed spare you from clicking back and forth as often among tabs in your browser, it doesn’t entirely eliminate clicking around. Its sidebar can display only one type of information at a time — social networks and photo-sharing sites in one view, news feeds in a second, the clipboard in a third, and Web bookmarks in a fourth. So you’ll have to click the sidebar’s own controls fairly often to check all of these, or keep going to the special My World page in the main window.

Finally, Flock works with only certain social networking, photo-sharing and blogging services. While it does support most of the main ones, there are some glaring omissions. MySpace isn’t yet on the list, though it’s expected to be added next month. But Hotmail, Windows Live Spaces and SmugMug, among others, are missing. And it doesn’t support any instant-messaging services at all.

Flock does a good job at the tasks it sets for itself, but I would recommend it for only the heaviest and most impatient social networkers. For most others, Flock is overkill.

Find all of Walt Mossberg’s columns and videos online, free, at the All Things Digital Web site, walt.allthingsd.com. Email him at mossberg@wsj.com.

Such Web-based software has existed for years, but it was clumsy, slow and simplistic — no match for locally installed software. Common techniques, such as dragging items around the screen, were impossible. Seeing the results of an action often required the Web page to reload.

Now, developers are churning out Web-based applications that are so fast, rich and smooth they can hardly be distinguished from standard programs. And because they live online, these Web applications can be constantly updated; can run on both Windows and Mac computers; and can be easily integrated with other Web sites and services.

One of the best examples of these slick new Web-based application is Picnik, a sophisticated, photo-editing application offered free of charge at picnik.com. I have been testing Picnik and I like it a lot. It’s a fast and impressive program for tweaking and improving your photos, then posting them to popular photo Web sites, saving them to your own computer, emailing them, or even printing them.

Picnik, which comes from a small Seattle company called Bitnik, isn’t meant to compete with Adobe Photoshop, or to serve professional photographers or dedicated hobbyists. Instead, it’s for the same casual photographer who would use the limited editing tools in Apple’s iPhoto or Microsoft’s Windows Vista Photo Gallery.

Picnik isn’t a place to store your pictures, or a way to organize them — yet. The company says it will consider adding these features down the road. For now, it is focused on being an editing complement to popular Web services — such as Yahoo’s Flickr, Google’s Picasa Web Albums, and the independent Facebook — that already allow for storing and organizing photos. You could also easily use it as the main editor for photos you store on your hard disk.

The program is currently in beta, or test, phase, though in my tests it worked smoothly and surely. During this beta period, all of its features are offered for free. Later this summer, the company expects to end the beta period and begin charging something like $20 or $25 a year for access to some of the more rarified special effects that Picnik offers, though the core editing and sharing functions, and some of the effects, will remain free.

In my view, Picnik has a beautiful and responsive user interface that worked perfectly on the multiple Windows and Macintosh computers I used to test it. It worked equally well in the latest versions of the three best-known Web browsers: Microsoft’s Windows-only Internet Explorer, Mozilla’s Firefox (on both Windows and Mac) and Apple’s Safari (on both Mac and Windows.)

Picnik uses a simple tabbed interface across the top to navigate among its major functions. Edits and changes are previewed in real time, instantly, without the need for a page refresh or reload. Actions are confirmed with translucent messages that pop up on the screen and fade gracefully.

Any edit or special effect can be undone or redone instantly, all the way back to the original version of the picture, which Picnik retains on its servers during the editing process.

For example, you can zoom in or zoom out on a picture with a slider that works just as it would in a local program — the effect is immediate, with no jerkiness. If you wish to crop a picture, a pane representing the region to be included in the crop is superimposed on the photo. Everything inside the pane is sharp and clear, and everything else is faded a bit. This pane can be dragged, or resized, in real time.

Another example: If you want to tint a picture, the program shows you a color palette with a white dot you can move around the palette to pick your tint. As you do this, or move a slider that controls the intensity of the tint, the changes are instantly previewed in the picture.

None of this is unusual for a standard photo program installed on your computer, but it is impressive to see these effects happen so quickly and interactively in a program functioning over an Internet connection.

Picnik’s makers have struck partnerships with Flickr, Picasa and Facebook, and you can easily fetch pictures from these sites and post new pictures or edited versions of the originals back to the sites. You don’t need to switch to the sites themselves, they appear inside the Picnik Web page.

You can also upload pictures for editing from any other Web site, or from your hard disk, and you can email pictures to friends or to a wide variety of other sites, such as PhotoBucket, SmugMug and Snapfish.

The designers of Picnik have done such an elegant job that I wish the site would allow storage of photos, or organization of photos across your multiple online accounts and your hard disk. If you want to see how good a Web application can be, take Picnik for a spin.

• Email me at mossberg@wsj.com. Find all my columns and videos online free at the new All Things Digital Web site, http://walt.allthingsd.com.

Here are a few questions about computers I’ve received recently from people like you, and my answers. I have edited and restated the questions a bit, for readability. This week my mailbox contained questions about choosing a photo-sharing Web site, syncing laptops and desktops and printing photos.

I’m unhappy with the photo-sharing Web sites that I’ve found and I wanted to ask if you’ve found any better ones. One problem I’ve run into is that they require you to sign in (create an account) to view your friends’ photos. They also don’t make it easy to download photos and they don’t allow much privacy.

You might try Smugmug at smugmug.com. It costs $40 a year, but offers unlimited storage, password protection, retrieval of photos in high-resolution format and it doesn’t require your friends to register or to receive spam. It is also a handsome site that allows you to customize the way your photos are presented and to tweak the photos themselves, to a limited extent.

What do you recommend for remotely syncing laptops and desktops?

I use a free product called FolderShare, which is now owned by Microsoft, and can be downloaded at www.foldershare.com. You install the FolderShare software on each computer, and it runs in the background, silently synchronizing all the files in folders that you designate on each computer. If you add or alter a file on one computer, the software matches that change on the others.

For instance, you might set it up to synchronize the files in the My Documents folders on multiple Windows machines. It also works on the Macintosh, and can synchronize files between Macs, or mixed groups of Windows and Mac computers. For instance, you can set it up to keep the My Pictures folder on a Dell synchronized with the Pictures folder on a Mac.

While on vacation I uploaded many photos to my Dell laptop. I also have a Dell desktop at home hooked up to a H-P Photosmart printer. When I get home, how can I print these photos? Do I have to transfer them to the desktop or can I just print them from the notebook? If so, how do I go about it?

Assuming the printer isn’t on a home network, and isn’t accessible from any PC on the network, you have two choices. The simplest method would be to transfer the pictures to the desktop computer, by copying them to a thumb-sized USB drive or burning them to a CD, from the laptop, and then copying them from the thumb drive or CD onto the desktop.

The other approach would be to install the printer’s software onto the laptop, assuming you still have the disk that came with it, and then unplug the printer from the desktop and plug it into the laptop.

* * *

Because of the volume of email I receive, I can’t routinely answer individual questions by email, or consult on individual problems or purchasing decisions. I read all questions I receive and select three each week to answer in the column.

Write to Walter S. Mossberg at mossberg@wsj.com