There's a saying in photography that the best camera is the one you have with you the most. For many people, that's the camera on their smartphone. Luckily for iPhone owners, the camera that comes with your smartphone is pretty impressive.

The original iPhone had a very simple camera. It took photos, but it lacked features like user-directed focus, zoom, or a flash. The iPhone 3GS added one-touch focus, but it took until the iPhone 4 for the iPhone camera to add important features like flash and zoom.

The iPhone 4S added a few nice features like HDR photos, while the iPhone 5 brought support for panoramic images. Whichever feature you're interested in, here's how to use it:

Switching Cameras

The iPhone 4, 4th generation iPod touch, and iPad 2, and all newer models, have two cameras, one facing the user, the other on the back of the device. This is used both for taking pictures and using FaceTime.

Choosing which camera you're using is easy. By default, the higher-resolution camera on the back is selected, but to choose the user-facing one (if you want to take a self portrait, for instance), just tap the button in the top right corner of the Camera app that looks like a camera with rotating arrows around it. The image on the screen will change to the one picked up by the user-facing camera. To change back, just tap the button again.
Works with: iPhone 4 and higher
 

Zoom

The iPhone camera can not only focus on any element of a picture when you tap it (more on that in a moment), you can also zoom in or out.

To do this, open the Camera app. When you want to zoom in on an aspect of the image, simply pinch and drag to zoom in as you would in other apps (i.e., put thumb and forefinger together on the screen and then drag them apart towards opposite ends of the screen). This will both zoom in on the image and reveal a slider bar with a minus on one end and a plus on the other will appear at the bottom of the image. This is the zoom. You can either keep pinching and dragging, or slide the bar left or right, to zoom in and out. The image will automatically adjust as you do this. When you have just the photo you want, tap the camera icon at the bottom center of the screen.
Works with: iPhone 3GS and higher
 

Flash

The iPhone camera is usually pretty good at picking up the details of an image in low light (especially on the iPhone 5, which has enhancements designed specifically for those conditions), but thanks to the addition of a flash, you can get great low-light photos. Once you're in the Camera app, you'll find the flash icon at the top left of the screen, with the lightning bolt on it. There are a few options for using the flash:

• Off - This is pretty self-explanatory, I think. And is the default setting for the camera.
• Auto - Tap the flash icon to reveal its options. Select Auto if you want the flash to be used only when needed, as determined by the iPhone.
• On - When you select this, the flash will be used with every picture you take.

Works with: iPhone 4 and higher
 

HDR Photos

HDR, or High Dynamic Range, photos take multiple exposures of the same scene and then combine them to create a better looking, more detailed image. HDR photography was added to the iPhone with iOS 4.1.

If you're running iOS 4.1 or higher, when you open the Camera app, you'll find a button reading HDR On at the top middle of the screen. If you're running iOS 5-6, you'll see an Options button at the top of the screen. Tap it to reveal a slider to turn HDR photos on. In iOS 7, the HDR On/Off button has returned to the top of the screen.

To turn them off (you'll want to do this if you're trying to save storage space), tap the button/move the slider so it reads HDR Off.
Works with: iPhone 4 and higher
 

AutoFocus

To automatically bring the focus of a photo to a particular area, tap that area of the screen. A square will appear on the screen to indicate what part of the image the camera is focusing on. Autofocus also automatically adjusts exposure and white balance to attempt to deliver the best looking photo.
Works with: iPhone 4 and higher
 

Panoramic Photos

Want to capture a vista that's wider or taller than the standard image size offered by iPhone photos? If you're running iOS 6 on certain models, you can use the panoramic feature to take a very large photo. The iPhone doesn't include a panoramic lens; instead, it uses software to stitch together multiple photos into a single, large image.

To take panoramic photos, the steps you need to take depend on what version of the iOS you're using. In iOS 7 or higher, swipe the text below the viewfinder until Pano is highlighted. In iOS 6 or earlier, when you're in the Camera app, tap Options, and then tap Panorama.

Tap the button used to take photos. It will change to a button that says Done. Move the iPhone slowly and steadily across the subject you want to capture in panorama. When you've got your full image, tap the Done button and the panoramic photo will be saved to your Photos app. The photo will look jagged on your iPhone (which can't display a panoramic image due to the limits of its screen size). Email it or print it, though, and you'll see the full-size photo. Works with: iPhone 4S and higher running iOS 6 and higher
 

Square Format Photos (iOS 7)

If you're running iOS 7 or higher, you can take Instagram-style square photos instead of the rectangular photos the Camera app normally captures. To switch to square mode, swipe the words beneath the viewfinder until square is selected. Then use the camera as you normally would.
Works with:iPhone 4S and higher running iOS 7 and higher
 

Burst Mode (iOS 7)

The combination of iOS 7 and the iPhone 5S delivers some powerful new options for iPhone photographers. One of these options is burst mode. If you want to capture a lot of photos quickly--especially if you're photographing action--you'll love burst mode. Instead of just snapping a picture every time you press the button, with it you can take up to 10 photos per second. To use burst mode, use the Camera app like normal except when you want to take photos, just tap and hold on the button. You'll see an onscreen count rapidly rise. This the number of photos you're taking. You can then go to the Photos app to review your burst-mode photos and delete any you don't want.
Works with: iPhone 5S and higher
 

Filters (iOS 7)

Some of the most popular recent photo apps allow you to apply stylish effects and filters to your photos to make them look cool. To use filters, tap the icon of the three interlocking circles at the bottom corner of the app. You'll have 8 filter options, with each one showing a preview of what it will look like applied to your photo. Tap the one you want to use and the viewfinder will update showing you the photo with the filter applied. Use the camera app as you otherwise would. The photo saved to the Photos app will have the filter on them.
Works with: iPhone 4S and higher running iOS 7 and higher
 

Grid

There's another choice in iOS 5 and higher's Options menu: Grid. In iOS 7, Grid is turned on by default (you can turn it off the Photos & Camera section of the Settings app). Move its slider to On and a grid will be overlaid on screen (it's just for composition; the grid won't appear on your images). The grid breaks the image up into nine equally sized squares and can help you compose your photos.
Works with: iPhone 3GS and higher
 

AE/AF Lock

In iOS 5 and higher, the Camera app includes an AE/AF lock feature to let you lock in auto-exposure or autofocus settings. To turn this on, tap on the screen and hold until you see AE/AF Lock appear at the bottom of the screen. To turn the lock off, tap the screen again. (This feature has been removed in iOS 7.)
Works with:iPhone 3GS and higher
 

Recording Video

The iPhone 5S, 5C, 5, and 4S back camera can also record video at up to 1080p HD, while the iPhone 4 camera records at 720p HD (the 5 and higher's user-facing camera can also record video at 720p HD). The way you change from taking still photos to video depends on which version of the iOS you're using. In iOS 7 and higher, slide the words just below the viewfinder so that video is highlighted. In iOS 6 or earlier, look for the slider at the bottom right corner of the screen. There you'll see two icons, one that looks like a camera, the other that looks like a square with a triangle coming out of it (designed to look like a movie camera). Move the slider so that the button is under the movie camera icon and the iPhone camera will switch to video mode.

To begin recording video, tap the button with the red circle in it. When you're recording, the red button will blink and a timer will appear onscreen. To stop recording, tap the button again.

Some of the still photography features of the app, like HDR photos or panorama, don't work when recording video, though the flash does.

Video shot with the iPhone camera can be edited using the iPhone's built-in video editor, Apple's iMovie app (Purchase at iTunes), or other third-party apps.
 

Slow Motion Video (iOS 7)

Along with burst mode, this is the other major improvement delivered by the combination of iOS 7 and the iPhone 5S. Rather just taking traditional 30 frames/second videos, the 5S can take slow motion videos running at 120 frames/second. This option can add drama and detail to your videos and looks great. To use it, simply swipe the row of options below the viewfinder to Slo-Mo and record video like normal.
Works with: iPhone 5S and higher
 
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