iPhoneography
I have an iPhone 3GS,
Most of all, photography with the iPhone is fun!
Apps
The camera app that comes with the iPhone has the basic ability to take photos. It saves them and that's about it. You can do more with the camera and photos with the many apps that you can download from the app store. I have just started playing around with the iPhone camera and use the following apps:
ToyCamera - Select from a menu of effects, or go with random!
Hipstamatic - Change lenses, flash and film to get different retro looking effects.
Camera Genius - Has tons of features to improve the basic iPhone camera including anti-shake, timer, burst mode and composition guides
Best Camera - Has 14 filters that can be combined for unique effects, and can be configured to share to your Twitter and Facebook accounts.
TiltShift Generator - Makes scenes look like miniatures by applying a tilt-shift filter.
Pano - Stitches together up to 16 photos to generate panorama photos.
PS Express - A collection of filters to quickly edit your iPhone photos.
BlurFX - Create selective focus effects quick and easily.
Aisu Sepia - Gives your photos a vintage sepia look.
Sharing
The iPhone makes it easy to share your photos - you can post to your blog, Facebook, Flickr, Twitter, Tumblr or e-mail them to your friends!
Spontaneity
You can use the iPhone in situations where taking out your buy ambien online regular camera would destroy the spontaneity. People don't pay as much attention to you when you are using the iPhone, but they stop and change their behaviour when you take out a DSLR with a big lens! With the iPhone, you are hardly noticed, so you can capture the mood without influencing it too much.
More of my iPhone Photos on Flickr
Disadvantages
There are some trade-offs with the iPhone camera. Don't expect the quality to be anywhere close to what you would get with a modern digital camera.
Low res - The major disadvantage with the iPhone camera is its low resolution. The iPhone 3GS digital camera is 3MP and the iPhone 4 is better at 5 MP. That's fine for online sharing and small prints, but it you want large prints the iPhone may not be the best choice! For best results, make sure you select the highest resolution image setting for each app. The default is usually one of the lower resolutions settings.
High noise - The small sensor results in high noise levels in the photos, which is noticeable when you view the photos at 100% on a monitor. The noise does add to the grainy retro feel to the photos, but you may not always want that. I use Lightroom 3 to remove the noise with successful results.
Lens quality - the tiny lens is quite remarkable, but obviously is limited in comparison to DSLR cameras. iPhone photos will not have the sharpness and depth of field effects that you get with a DSLR.
Lack of flexibility - the major advantage of more sophisticated cameras such as DSLRs, is their ability to take photos in many challenging situations. You can switch lenses, use external strobes, change the ISO, shutter speed and aperture, and shoot in RAW format. The the iPhone 4 does have an LED flash to give it some more flexibility in low light. With the iPhone, you must take advantage of existing light and let the camera determine the best settings.
Conclusion
I love the spontaneous randomness of the iPhone. Combined with the many apps, I can generate images that I would not be able to capture any other way, especially when I don't have my other camera with me ready to go!