APPLE I PAD

The iPad is a tablet computer designed and marketed by Apple, meant for internet browsing, media consumption, gaming, and light content creation. Unlike many older tablets, it does not use a stylus for input and instead uses fingertips. Released in April 2010, it introduced a class of devices between smartphones and laptops.

Like the older iPod Touch and iPhone devices, the larger iPad runs the iPhone OS and uses a multi-touch LCD for most user interactions. It runs iPad-specific applications as well as those written for the iPhone and iPod touch, including e-book readers.

The iPad uses WiFi or Wireless WAN to browse the Internet, load and stream media, and install software.

The touchscreen is a 25 cm (9.7 in) liquid crystal display (1024 × 768 pixels, 132 ppi, XGA) with fingerprint–resistant and scratch-resistant glass. Like the iPhone, the iPad is designed to be controlled by bare fingers, not gloves and styli that prevent electrical conductivity (although there are gloves and styli designed for this use).

The display responds to two other sensors: an ambient light sensor to adjust screen brightness and a 3-axis accelerometer to sense iPad orientation and switch between portrait and landscape modes. Unlike the iPhone and iPod touch, which work in three orientations, the iPad supports screen rotation in all four orientations, meaning that the device has no intrinisc "up" or "down"; only the position of the home button changes. Most, if not all, iPad applications support both portrait and landscape mode.

The iPad has a switch to lock out this screen rotation function (reportedly to prevent unintended rotation when the user is lying down).There are a total of four physical switches, including a "home" button below the display that returns the user to the main menu, and three plastic physical switches on the sides: wake/sleep and volume up/down, along with the screen rotation lock.

The iPad can use Wi-Fi network trilateration to provide location information to applications such as Google Maps. The 3G model contains A-GPS while both models have a digital compass.

The back of the Wi-Fi model iPad is made of contoured aluminum with black plastic buttons. The Wi-Fi + 3G model also has a black plastic accent on top of the device.

Dual speakers housed inside the iPad provide monaural sound via two small sealed channels in the interior speaker assembly that direct the sound outwards toward the three audio ports carved into the bottom-right corner of the unit.The microphone is within the device. A volume switch is on the right side of the unit, and a 3.5 mm TRS connector audio-out jack provides stereo sound for headphones on the top-left corner of the device. The iPad supports normal headphones and models with microphones, volume controls, or both. Microphones can be used for voice recording.

The built-in Bluetooth 2.1 + EDR interface supports the HSP, A2DP, and HID profiles, which allow wireless headphones and keyboards to be used with the iPad. However, the iPhone OS does not currently support the OBEX file transfer protocol.

Composite video up to 576i can be taken from the dock connector via a VGA adaptor sold by Apple, but there is no HD output option.

The iPad uses an internal rechargeable lithium-ion polymer battery. The iPad is designed to be charged with a high current (2 amperes) using the included USB 10 W power adapter. While it can be charged by a standard USB port from a computer, these typically provide lower current (500 milliamperes or 1 ampere). As a result, if the iPad is turned on while being charged with a normal USB computer port, it will charge much more slowly, if at all.

Apple claims that the iPad's battery can provide up to 10 hours of video, 140 hours of audio playback, or one month on standby. The battery loses capacity over time and is not designed to be user-replaceable. As in the battery-replacement program for iPod and the original iPhone, Apple will replace an iPad that does not hold an electrical charge with a refurbished iPad for a fee of US$99.

The iPad was released with three options for internal storage size: a 16, 32, or 64 GB flash drive. All data are stored on the flash drive and there is no option to expand storage. Apple sells a camera connection kit with an SD card reader, but it can only be used to transfer photos and videos.

The Wi-Fi + 3G model has a micro-SIM slot (not mini-SIM) located on the side of the device. Unlike the iPhone, which is usually sold locked to specific carriers, the 3G iPad is sold unlocked and can be used with any compatible GSM carrier.