this paper is based on the systematic evolution of operating systems for mobile devices. In this paper few of the most common operating systems were selected for the study and a detailed timeline of their evolution based on the requirements of that era is discussed. The paper also focus on the current features and trends of the selected mobile phone operating systems.
Mobile phone operating systems is one of the area in the technology that has grown tremendously in the last decade and that is obviously due to the increasing demand in the services and the mobile phone user. It is not the similar time in which the mobile phones were just used to make phone calls, today there are hundreds of applications available for mobile phones, each with their own purpose. It was in 1996 when Palm OS , the first ever mobile phone operating system was introduced and today in 2011 there is Windows Phone.
There is a battle of mobile phone operating systems, each providing better and more features than the other. There is Android by Google, Black Berry by RIM, iPhoneOS by Apple, Windows Mobile by Microsoft and many others
2. Evolution of Mobile Phone Operating Systems
For this paper, few famous and most commonly used operating systems are selected, and a detailed study is performed on their development and growth within the last one decade.
2.1 Palm OS
Palm OS is one of the earliest mobile phone operating systems, it was launched in early 1996. The operating system has been used and implemented with an extensive range of mobile devices like wrist watches, handheld games ,pagers, digital cameras,GPS devices, smart phones etc.
2.1.1 Evolution of Palm OS
The version 1.0 of PalmOS was presented on early PDA's produced by Palm Inc. it was build on the kernel of AMX 6800 RTOS. It used the Freescale DragonBall processors. The processor is capable of speeds of up to 16.58Â MHz and can run up to 2.7 MIPS million instructions per second.
PalmOS 2.0 introduced the TCP/IP network. PalmOS 3.0 came with infrared and enhanced font support. This version also features PIM applications. PalmOS 4.0 added a standard interface for external file system access (such as SD cards). Palm OS 5 was the first version released that used the ARM architecture-based processors. The ARM is a 32-bit reduced instruction set computer (RISC).
Palm OS Cobalt: It was introduced in 2004, it had all the functionality of a modern operating system, it was based on a new kernel with multitasking and memory protection, a modern multimedia and graphic framework, new security features, and adjustments of the PIM file formats to better cooperate with Microsoft Outlook.
2.1.2 Features of PalmOS: main features of the operating system are listed below
a) Multithreaded, Multitasking: it is designed to enable multiple applications to run simultaneously
b) Expanded, Protected Memory Architecture : With more memory the new protected memory architecture gives protection against applications "hanging" the system or causing crashes.
c) System Wide Security Architecture: it provides built-in encryption, authentication and authorization frameworks for securing applications.
d) Pluggable Communications Design: it is designed to supports multiple simultaneous communication sessions on various wireless networks
e) Extensible Multimedia Framework: it is designed to provide a rich graphics and multimedia architecture.
f) File management System : there is still no file management system in RAM. This means that Applications are directly installed into the RAM. The operation system relies on the periodic RAM refresh cycles to keep its memory, as there is no file system. It limits the types of files that can be stored in RAM.
2.2 Symbian OS
It is one of the most commonly used mobile phone operating systems in the world
2.2.1 Evolution of Symbion OS
Symbian OS is an open source operating system for mobile phones, the operating system is currently being handled by Nokia and is used with Nokia smart phones. this operating system has evolved from Psion's EPOC which was developed as a basic operating system for early electronic organizers.
EPOC16 : it was the operating system developed in the late 1980s for Psion's "SIBO" devices, a family of personal digital assistants. It had a 16-bit architecture and it was a preemptive, multitasking operating system, it was written in Intel 8086 assembler language. The very first EPOC16 devices came into the market in 1989.
EPOC32: The first version of EPOC32 was released in 1997. Although the names are similar but EPOC32 was completely different from EPOC16. It was written in C++ and the key advantage of EPOC32 was its ability to multi-task, perform multiple functions at once . EPOC32 was developed for the ARM processors family. In June 1998, Psion Software became Symbian Ltd., a collaboration between Psion and Ericsson, Motorola, and Nokia. Afterwards EPOC became famous by the name Symbian OS.
Symbian OS 6.0 : The first Symbian OS phone was the Nokia 9210 Communicator, it was released in 2001. The operating system kernel was Symbian 6.0 and the CPU Instruction set supported by it was ARM.
Symbian OS 7.0 : it was released in 2003 , it offered improvments for telephony and networking, Java, Multimedia
Symbian OS 8.0: it was released in 2004, it had a choice of two kernels EKA1 or EKA2. The kernels behave identically from user point of view but are internally they are very different. EKA1 offered compatibility with old device drivers and EKA2 was a real time kernel.
The Symbian platform: by combining the software resources of Nokia , Sony Ericsson and Symbian Ltd, the symbian platform was introduced. It has released three versions till now Symbian^1, Symbian^2 and Symbian^3
Symbian kernel : The Symbian kernel (EKA2) is sufficiently-fast real time kernel in which a single processor core can execute both the user applications and the signaling stack. It has a microkernel architecture that contains only basic primitives and functionality, for maximum robustness and responsiveness It contains a scheduler, memory management operations and device drivers, with networking, telephony and file system .
The OS architecture contains the following layers
UI Framework Layer
Application Services Layer
OS Services LayerBase Services Layer
Kernel Services & Hardware Interface Layer
2.3 BlackBerry OS
It is a proprietary mobile operating system, for its BlackBerry line of smartphone handheld devices. The operating system provides multitasking and supports specialized input devices, like the trackwheel, trackball, and most recently, the trackpad and touchscreen.
2.3.1 Evolution of Black Berry
the Black berry era started when in 1996 RIM released a two-way messaging pager called The Inter@ctive Pager, in 1999, the first black berry device called 850 was introduced. In 2002, smartphone BlackBerry was released, it supported email, mobile telephone, text messaging, Internet, Web browsing and other wireless information services. The original BlackBerry devices, the RIM 850 and 857, used the DataTac network. DataTac is an open standard for point to point wireless data communications. BlackBerry made place in the market by focusing on email. RIM currently offers BlackBerry email service to non BlackBerry devices, through its BlackBerry Connect software. The original BlackBerry had a monochrome display, but now all models have color displays
2.3.2 Balc Berry System Features :
The operating system used by BlackBerry devices is a proprietary multitasking environment developed by RIM. Early BlackBerry used Intel-80386-based processors. BlackBerry 8000 series smartphones, are based on the 312Â MHz ARM XScale. The BlackBerry Curve 8520 features a 512Â MHz processor. The operating system is designed for use of input devices such as the track wheel, track ball, and track pad. The OS provides support for Java MIDP 1.0 and WAP 1.2. it also provides synchronization with Microsoft Exchange Server email and with Lotus Domino email. The current OS 5.0 provides some functions of MIDP 2.0, and allows complete activation and synchronization with Exchange email, calendar, tasks, notes and contacts, and adds support for Lotus Notes. Updates to the operating system may be automatically available from wireless carriers that support the BlackBerry OTASL (over the air software loading) service.
Third-party developers can write software using the available BlackBerry API, although proper authentication and verficaiton is required.
2.4 Windows Mobile is a mobile operating system developed by Microsoft that was used in smartphones and mobile devices
2.4.1 Evolution of Windows Mobile
Pocket PC 2000 was launched in April 2000. Â This was based on the Windows CE 3.0 platform. Â It looked and worked like Windows 98. Pocket PC devices were not standardized with a specific CPU architecture so it was released on multiple CPU architectures;Â SH-3,Â MIPS, andÂ ARM. Pocket PC 2002 was launched in October 2001. Â The UI was changed according to the new Windows XP operating system. Windows Mobile 2003 was launched in June 2003. This was when the name was changed from Pocket PC to Windows Mobile. Â Windows Mobile 5- launched May 2005. Â This is the first version to allow users to attach to an Exchange server to allow for push notifications. Windows Mobile 6.5- launched May 2009. Â This is what is currently in use on all Windows Mobile phones today in some form or fashion with point release versions 6.51, 6.53 and 6.55 available from the OEMs/vendors and their branding upon the operating system
Windows Phone 7: this OS has not been fully launched in all of the world, It has been built from scratch and bears no resemblance to its predecessors.
Windows Mobile Features :
Office Mobile a suite of Mobile versions of Microsoft Office applications. Outlook Mobile comes with Windows Mobile. Internet Explorer Mobile is an Internet browser developed by Microsoft for Pocket PC. Windows Media Player for Windows Mobile. Client for PPTP VPNs. The file system similar to that of Windows 9x/Windows NT and support for many of the same file types. It has the Ability to multitask. S is available for the Windows Mobile operating system.
Microsoft usually release Windows Phone software development kits (SDKs) that work together with Visual Studio development environment.
Android Operating System
In 2005 Google bought Android, Inc. and began developing a Linux-based operating system for cell phones and other mobile devices. Their main marketing targets were handset makers and carriers. In November in 2007, Google, HTC, Motorola, Intel, Qualcomm, Sprint Nextel, T-Mobile, and NVIDIA, came together to form the Open Handset Alliance. They stated their goal for developing open standards for mobile devices, and initiated a new product called Android, which is a mobile device platform built on the Linux kernel.
Features of Android
The OS has a lightweight relational database called SQLite.
It supports connectivity technologies including GSM, CDMA, UMTS, Wi-Fi, Bluetooth, LTE, and WiMAX.
It has a Web browser and Java support.
It handles media formats like H.264, MP3, MIDI, WAV, MPEG-4 SP, JPEG, PNG, GIF, BMP. It also supports RTP/RTSP streaming
Other features include video calling, Bluetooth, mulitouch etc.
Multitasking of applications in Android is available.
It also supports tethering, which allows a phone to be used as a wireless/wired hotspot.
There is a large community of android developers and currently there are over 250,000 apps available.
The Android software development kit (SDK) have a complete set of development tools
After the study of the selected mobile phone operating systems, it was observed that the pace of development in this field is enormously fast and is in a continuous process of growth. Every day more and more features are being packed into these small devices. Most of this development is driven by user requirements and the aspect of business approach cannot be ignored, every corporation desires to come up with better and more than the previous.