Five apps iPhone photographers love

First up is the coolest app of them all. Microsoft recently released Photosynth for the iPhone, an app that lets you create "synths" using just your phone. In a nutshell, Photosynth takes a collection of photos taken around the same location and, sort of like a traditional panoramic program, stitches them into a coherent scene. A Photosynth image can be 360 degrees and interactive, though you can pivot around the scene from the point of view of the photographer, looking up and down and all around, and zoom in for a better view.

Microsoft's Photosynth for the iPhone delivers all that in the palm of your hand. The app lets you take a slew of photos and then stitch them together. You can take just a few shots or diligently fill in every corner of your surroundings. Photosynth shows you what regions are captured and where the gaps in your scene are even as you shoot. When you're done, it takes a few moments to process, and then you can interact with your synth on your iPhone or upload it Microsoft's Photosynth site to share your handiwork. It's all free—and it feels a little like science fiction.

When Adobe first released Photoshop Express for the iPhone, I thought it was a bit of a curiosity—a fun diversion, but not especially practical or useful. These days, Photoshop Express makes it possible to clean up your iPhone photos in a meaningful way. Of course, Photoshop Express doesn't include any of the goodies you'll find in CS5 or even Photoshop Elements. What you will find are all the essential basic photo editing tools, smartly implemented in a way that makes sense on a phone's touchscreen. There are ways to crop, straighten, rotate, and flip a photo. You can change exposure, saturation, and tint by sliding your finger across the screen until you see what you like. There are some special effects like soft focus and sketch mode. Buy the Adobe Camera Pack for $2 to get extra features like a noise reduction filter and self-timer for taking photos.

I am a huge fan of the online storage tool Dropbox. The Dropbox iPhone app has a great feature tailored just for photographers. Start the app and go to the Uploads tab, where you can send multiple photos from your camera roll directly to any folder in your Dropbox account. Once you start the upload, it continues in the background while you go off and do other things. In the past, you could move photos to Dropbox (or other cloud storage solutions) only one photo at a time, so this is a great way to back up your iPhone photos or share them quickly with another computer that shares your Dropbox account.

Everyone, it seems, loves photos with selective color. You no longer need a program like Photoshop and a working knowledge of layers to create this effect, because apps like Color Splash can do it for you more or less automatically. Color Splash is a fun little app. For $2, you paint with your finger to erase the color from your photo or selectively bring the color back. After using Color Splash to remove the color from a few of your photos, you'll probably wish your desktop photo editor worked just as easily.

Finally, there's Instagram. This app is crazy popular—no fewer than three of my friends mentioned it to me this week alone. Like peanut butter and chocolate, Instagram combines two things people like: photo effects and sharing. The app lets you apply a dozen vintage-looking photography and novelty visual effects to your images, then post them to Twitter, Facebook, Flickr, and a handful of other online destinations. Best of all, it's free.