| Palm OS is a compact operating system | | | | than on previous generation hardware. New |
| developed and licensed by PalmSource, Inc. for | | | | software can take advantage of the ARM |
| personal digital assistants (PDAs) manufactured by | | | | processors with PNO (PACE Native objects), small |
| various licensees. It is designed to be easy-to-use | | | | units of ARM code, these are also sometimes |
| and similar to desktop operating systems such as | | | | referred to as 'ARMlets'. It was also around this |
| Microsoft Windows. Palm OS is combined with a | | | | time when Palm began to separate its hardware |
| suite of basic applications including an address | | | | and OS efforts, eventually becoming two |
| book, clock, note pad, sync, memo viewer and | | | | companies, PalmSource, Inc. (OS) and palmOne |
| security software. Palm OS was originally released | | | | (hardware, now named Palm, Inc.). Further |
| in 1996. | | | | releases of Palm OS 5 have seen a standardised |
| Versions history | | | | API for hi-res and dynamic input areas, along with |
| Palm OS was originally developed by Jeff Hawkins | | | | a number of more minor improvements. |
| for use on the original Motorola DragonBall-based | | | | Palm OS 5.2 and 4.1.2 (and later) also feature |
| Pilot PDA by U.S. Robotics. Palm OS 1.0 was | | | | Graffiti 2. This is based on Jot by CIC. |
| present on the original Pilot 1000 and 5000. | | | | Palm OS 5.4 added the Non-Volatile File System, |
| Palm OS 2.0 was introduced with the PalmPilot | | | | and used Flash for storage instead of DRAM, |
| Personal and Professional. | | | | preventing data-loss in the event of battery drain. |
| Palm OS 3.0 was introduced, ith the launch of the | | | | However, this fundamentally changed the way |
| Palm III series. Incremental upgrades occurred | | | | programs were executed from the |
| with the release of versions 3.1, 3.3, and 3.5, | | | | Execute-in-Place system that PalmOS traditionally |
| adding support for color, multiple expansion ports, | | | | used, and has been the source of many |
| new processors, and other various additions. | | | | compatibility problems, requiring many applications |
| Palm OS 4.0 was released with the m500 series, | | | | to have explicit NVFS support added for them to |
| and later made available as an upgrade for older | | | | be stable. |
| devices. This added a standard interface for | | | | In December 2006, Palm (Hardware) paid $44 |
| external filesystem access (such as SD cards) | | | | million to ACCESS for the rights to the source |
| and improved telephony libraries, security, and the | | | | code for Palm OS (6.0) Garnet. With this |
| UI. Version 4.1 included a series of bug fixes. | | | | arrangement, a single company is again developing |
| Palm OS 5.0 was introduced in November 2002 | | | | palm hardware and software. Palm can modify |
| with the Tungsten T and was the first version | | | | the licensed software as needed and it need not |
| released to support ARM devices. Described as a | | | | pay royalties to ACCESS over future years. |
| stepping stone to full ARM support, DragonBall | | | | Palm OS 1.0 to 4.1 were based on top of a small |
| Palm apps are run in an emulated environment | | | | kernel licensed from KADAK Products Ltd. While |
| called the Palm Application Compatibility | | | | these versions are technically capable of |
| Environment (PACE), making the device capable | | | | multitasking, the "terms and conditions of that |
| of running software written for older versions. | | | | license specifically state that Palm may not |
| Even with the additional overhead of PACE, Palm | | | | expose the API for creating/manipulating tasks |
| applications usually run faster on ARM devices | | | | within the OS." |