Palm OS comes with these applications built-in: Dates, Address Book, To Do Lis, Memo Pad, Calculator, and Password Protection. New applications can be written and added using several facilities that accelerate development.

images22Manufacturers are free to implement different features of the OS in their devices or even add new features. This version history describes the officially licensed version from Palm/PalmSource/ACCESS.

PalmOSPalm OS (also known as Garnet OS) is a mobile operating system initially developed by Palm, Inc. for personal digital assistants (PDAs) in 1996. Palm OS is designed for ease of use with a touchscreen-based graphical user interface.
PalmOS Palm OS was originally developed under the direction of Jeff Hawkins at Palm Computing, Inc.  Palm was later acquired by U.S. Robotics Corp., which in turn was later bought by 3Com, which made the Palm subsidiary an independent publicly traded company on March 2, 2000.

PDA

A personal digital assistant (PDA), also known as a palmtop computer, is a mobile device which functions as a personal information manager and has the ability to connect to the internet. The PDA has an electronic visual display enabling it to include a web browser, but some newer models also have audio capabilities, enabling them to be used as mobile phones or portable media players. Many PDAs can access the internet, intranets or extranets  via Wi-Fi, or Wireless Wide Area Networks (WWANs). Many PDAs employ touch screen technology.
PalmOS OverviewPalm OS is a proprietary mobile operating system. Designed in 1996 for Palm Computing, Inc.'s new Pilot PDA, it has been implemented on a wide array of mobile devices, including smartphones, wrist watches, handheld gaming consoles, barcode readers and GPS devices.

Palm OS versions earlier than 5.0 run on Motorola/Freescale DragonBall processors. From version 5.0 onwards, Palm OS runs on ARM architecture-based processors.

The iPhone is a line of Internet  and multimedia-enabled smartphones  designed and marketed by Apple Inc., and originally released in 2007. An iPhone functions as a camera phone (also including text messaging and visual voicemail), a portable media player (equivalent to a video iPod), and an Internet  client (with e-mail, web browsing, and Wi-Fi connectivity).