On the bottom right of the new iPhone is a small speaker that's responsible for projecting speakerphone calls, music, movies, game noises, and any other miscellaneous noise. Because your device has just one speaker, it plays all audio in mono (on a single channel).
J) Back Camera and LED Flash
On the back of the iPhone 5 is the second of two cameras, as well as an LED flash. The camera sports an 8-megapixel CMOS backside illumination sensor, which snaps pictures at 3264-by-2448-pixel resolution. (In real-world terms, that would translate to a high-quality 8-by-10-inch glossy print.) An attached hybrid IR filter provides better color accuracy, while the f/2.4 aperture offers improved low-light performance. The iPhone 5 camera sports a sapphire lens cover for sharper images. The iPhone's back camera also captures 1080p high-definition video at up to 30 frames per second, with real-time video image stabilization and temporal noise reduction.
K) Ring/Silent Switch
The Ring/Silent switch--found on the left side of the device--does pretty much what you'd suspect: Flick it backward to silence the phone, forward to activate the ringer. When you switch to Silent mode, you reveal a small orange stripe on the switch, and your device vibrates. Silent mode silences only rings and alerts, however; you can still play music and game sounds through the speaker.
L) Volume Up and Volume Down Buttons
Directly below the Ring/Silent switch is a pair of volume buttons. Press the plus-sign button (+) to increase volume and the minus-sign button (--) to decrease volume. In the Settings app, you can choose whether these buttons affect only noises from an app, or whether they control systemwide sounds as well. In the Camera app, the plus-sign button also works as a physical shutter button.
M) SIM Card Slot
The new iPhone can operate on multiple cellular bands, thanks to its dynamically switching on-board radio: various bands of the LTE cellular data standard, HSPA+, DC-HSDPA, GPRS, EDGE, CDMA-EvDO, and HSPA. Major U.S. partners for the iPhone 5 include AT&T, Sprint, and Verizon.
When you purchase a new iPhone, you can do so in one of two ways: with a cellular carrier contract or contract free. The first option lets you receive a significant discount on the phone, but you have to use your iPhone solely with that carrier for two to three years, depending on your carrier and region. Contract-free phones allow you to use any carrier's pay-as-you-go plan but are several hundred dollars more expensive up front. Either way, you'll need a carrier to talk on your iPhone and use cellular data.