The iPad is designed, developed and marketed by Apple Inc., primarily as a platform for audio-visual media including books, periodicals, movies, music, games, apps and web content.
The iPad runs on iOS, the same operating system used on Apple’s iPod Touch and iPhone, and can run its own applications as well as iPhone applications. Without modification, the iPad will only run programs approved by Apple and distributed via the Apple App Store (with the exception of programs that run inside the iPad’s web browser).
Like iPhone and iPod Touch, the iPad is controlled by a multitouch display as well as a virtual onscreen keyboard in place of a physical keyboard.
iPad is available in Wi-Fi and cellular models. The Wi-Fi connection is used to access local area networks and the Internet. Cellular models have a 3G wireless network interface which can connect to HSPA or EV-DO data networks in addition to Wi-Fi.
The iPad can use Wi-Fi network trilateration from Skyhook Wireless to provide location information to applications such as Google Maps. The 3G model supportsA-GPS to allow its position to be calculated with GPS or relative to nearby cellphone towers; it also has a black strip on the back to aid 3G reception. The iPad has a headphone jack and a proprietary Apple dock connector, but no Ethernet or USB port. However, the Apple Camera Connection Kit accessory provides two dock connector adapters for importing photos and videos via USB and SD memory cards.
Audio and output
The iPad has two internal speakers reproducing left and right channel audio located on the bottom-right of the unit. In the original iPad, the speakers push sound through two small sealed channels leading to the three audio ports carved into the device, while the iPad 2 has its speakers behind a single grill. A volume switch is on the right side of the unit. A 3.5-mm TRRS connector audio-out jack on the top-left corner of the device provides stereo sound for headphones with or without microphones and/or volume controls. The iPad also contains a microphone that can be used for voice recording.
The built-in Bluetooth 2.1 + EDR interface allows wireless headphones and keyboards to be used with the iPad. However, the iOS does not currently support file transfer via Bluetooth. iPad also features 1024×768 VGA video output for limited applications, screen capture, connecting an external display or television through an accessory adapter.
Power and battery
The iPad uses an internal rechargeable lithium-ion polymer (LiPo) battery. The iPad is designed to be charged with a high current of 2 amperes using the included 10 W USB power adapter and USB cord with a USB connector at one end and a 30-pin dock connector at the other end. High-power USB ports in Apple computers and accessories provide full charging capabilities.
Apple claims that the battery for both generations of iPad can provide up to 10 hours of video, 140 hours of audio playback, or one month on standby. In a program similar to the battery-replacement program for the iPod and the original iPhone, Apple will replace an iPad that does not hold an electrical charge with a refurbished iPad.
Storage and SIM
The iPad model with data connectivity, unlike the Wi-Fi model, has a black plastic piece on the underside which allows cellular signals to pass through it.
The iPad was released with three capacity options for storage: 16, 32, or 64 GB of internal flash memory. All data is stored on the internal flash memory, with 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 side of the Wi-Fi + 3G model has a micro-SIM slot (not mini-SIM). The 3G iPad can be used with any compatible GSM carrier, unlike the iPhone, which is usually sold ‘locked’ to specific carriers.