iPhone 3GS

iPhone is back with a new OS (version 3.0). The touchscreen of 3GS is a 9 cm (3.5 in) liquid crystal display (320×480 px) with scratch-resistant glass with an ability to render upto 262,144 colours. Other then having a capacitive touchscreen  designed for a bare finger, or multiple fingers for multi-touch sensing, the iPhone 3GS also features a new Fingerprint-resistant oleophobic coating.

The display have three sensors connected to it. A proximity sensor deactivates the display and touchscreen when the device is brought near the face during a call. An ambient light sensor adjusts the display brightness which in turn saves battery power. A 3-axis accelerometer senses the orientation of the phone and changes the screen accordingly, allowing the user to easily switch between portrait and landscape mode. As usual the photo browsing, web browsing, and music playing support both upright and left or right widescreen orientations. The 3.0 also added landscape support for few applications like email etc.  Shaking the unit is now considered to be a form of input.

The iPhone 3GS has three physical switches on the sides: wake/sleep, volume up/down, and ringer on/off with a single “Home” hardware button below the display that brings up the main menu. For rest the touch screen furnishes most of the user interface. The iPhone 3GS feature a full plastic back to increase the strength of the GSM signal and is available in both colours (black & white), regardless of storage capacity. As for audio, one loudspeaker is located above the screen as an earpiece, and another is located on the left side of the bottom of the unit, opposite a microphone on the bottom-right. Volume controls are located on the left side of the unit and as a slider in the iPod application. The 3.5 mm headphones connector is located on the top left corner of the device. The headphone socket on the original iPhone is recessed into the casing, making it incompatible with most headsets without the use of an adapter. The iPhone 3GS eliminates the issue of recessed socket which made it incompatible with most headsets, with a flush mounted headphone socket. The headphone of 3GS also have a multipurpose button near the microphone that can be used to play or pause music, skip tracks, and answer or end phone calls without touching the iPhone itself.

The built-in Bluetooth 2.x+EDR supports wireless earpieces and headphones, which requires the HSP profile. Stereo audio was added in the 3.0 update for hardware that supports A2DP. 3GS does not officially support the OBEX file transfer protocol therefore prevents iPhone users from exchanging multimedia files, such as pictures, music and videos, with other bluetooth-enabled cell phones.

As always iPhone 3GS features an internal rechargeable battery which is not user-replaceable. The iPhone 3G’s battery is stated to be capable of providing up to ten hours of video, nine hours of web browsing on Wi-Fi or five on 3G, twelve hours of 2G talk time, or five on 3G, 30 hours of music, or 300 hours of standby. If the battery malfunctions or dies prematurely, the phone can be returned to Apple and replaced for free while still under warranty. The warranty lasts one year from purchase and is extended to two years with AppleCare.

The iPhone 3GS comes in 16 GB / 32 GB variants and all data is stored on the internal flash drive. The iPhone does not support expanded storage through a memory card slot. The SIM card is inserted into a slot at the top of the device and is usually sold with a SIM lock, which prevents the iPhone from being used on a different mobile network. All iPhone models comes with a written documentation, and a dock connector to USB cable. The iPhone 3GS includes the SIM eject tool and a revised headset, which adds volume buttons. The iPhone 3G and 3GS are compatible with the same dock, sold separately, but not the original model’s dock. All versions include a USB power adapter, or “wall charger,” which allows the iPhone to charge from an AC outlet.

The iPhone 3GS runs on iPhone OS 3.0. It is based on a variant of the same Darwin operating system core that is found in Mac OS X and also includes the “Core Animation” software component from Mac OS X v10.5 Leopard. It is capable of supporting bundled and future applications from Apple, as well as from third-party developers. Like the iPod, the iPhone 3GS is managed with iTunes. The interface of 3GS contains a graphical list of available applications. iPhone applications normally run one at a time, although most functionality is still available when making a call or listening to music. The home screen can be accessed at any time by a hardware button below the screen, closing the open application in the process. By default, the Home screen contains the icons Messages (SMS and MMS messaging), Calendar, Photos, Camera, YouTube, Stocks, Maps (Google Maps), Weather, Voice Memos, Notes, Clock, Calculator, Settings, iTunes (store), App Store, and an addition of Compass for 3GS. Also at the base of the screen, main purpose icons for Phone, Mail, Safari (Internet), and iPod resides. The 3.0 OS also adds a system-wide search, known as Spotlight, to the left of the first home screen.

The iPhone as a phone allows audio conferencing, call holding, call merging, caller ID, and integration with other cellular network features and iPhone functions. The voice control feature is available only on the iPhone 3GS which allows users to say a contact’s name for dialing the no. The iPhone also includes a visual voicemail feature allowing users to view a list of current voicemail messages on-screen without having to call into their voicemail. Unlike most other systems, messages can be listened to and deleted in a non-chronological order by choosing any message from an on-screen list. Customized ringtones from songs can be purchased from the iTunes Store for a small additional fee. The ringtones can be 3 to 30 seconds long from any part of a song.

iPhone 3GS implements a virtual keyboard on the touchscreen. It has automatic spell checking and correction, predictive word capabilities, and a dynamic dictionary that learns new words. The keyboard has predictability for word the user is typing and can correct the accidental pressing of keys adjacent to the presumed desired key. The keys are somewhat larger and spaced farther apart when in landscape mode. Touching a section of text for a brief time brings up a magnifying glass, allowing users to traverse through characters in a word. The virtual keyboard can accommodate upto 21 languages, including character recognition for Chinese. The 3.0 update brought support for cut, copy, or pasting text, as well as landscape keyboards in more applications. The text messages in 3GS are displayed in speech bubbles similar to a chat interface, under each recipient’s name. Text messages are presented chronologically in a mailbox format similar to Mail, which places all text from recipients together with replies. 3GS offers push email functionality using Apple’s MobileMe platform. The iPhone currently has built-in support for e-mail message forwarding, drafts, and direct internal camera-to-e-mail picture sending.

The iPhone 3GS has a 3.2 megapixel camera, with auto focus, auto white balance, and auto macro (up to 10 cm). It can also record VGA video at 30 frames per second. The iPhone includes software that allows the user to upload, view, and e-mail photos. The user has a functionality to zoom in and out of photos by sliding two fingers further apart or closer together, much like Safari. The Camera application also lets users view the camera roll, the pictures that have been taken with the iPhone’s camera.