The operatingsystem( OS) of a cell phone is a control software that makes the integrated hardware of the cell phone usable. This gives the processor access to the RAM, the keypad and microphone for text and voice input, the display and loudspeaker for output, the electronic components for sending and receiving via mobile radio, or the vibrator motor for the vibration alarm.
The cell phone operating system controls a cell phone's functions for managing addresses or appointments, multitasking and third-party software. Simple cell phones have proprietary operating systems with rigid memory management and a small range of additional software. The applications are often MIDlets of the Java Platform Micro Edition for a relatively slow bytecode interpreter program with limited memory. A separate Java processor executes the programs, but the interoperability of a Java-ME application with cell phones from other manufacturers cannot be guaranteed with Java-ME.
On a smartphone, the operating system also controls how the device is unlocked and where the user's addresses, appointments, e-mails and multimedia files are stored and synchronized. The operating system also provides the smartphone browser, multimedia player, digital camera and video camera, GPS functions, and Bluetooth and WLAN communication.
- Symbian from Symbian Ltd, a subsidiary of Nokia,
- Windows Mobile from Microsoft,
- Android from Google and other members of the Open Handset Alliance, and
- Brew MP from Qualcomm.
- Moblin from Intel for smartphones and other mobile devices with Internet access.
- MeeGo, which evolved from Nokia's Maemo and Intel's Moblin and was succeeded by Jolla and Tizen.
- Tizen from the Linux Foundation.
- Firefox OS from Mozilla.
Other smartphone operating systems are only suitable for the cell phones of a single manufacturer. These include:
Blackberry OS and BlackBerry 10 from Blackberry manufacturer RIM, iPhone OS or iOS 4 for the iPhone from Apple, webOS from Palm, Nova OS as the successor operating system to PalmOS, Maemo from Nokia and Bada from Samsung. The growing number of smartphone operating systems is causing increasing development costs for independent software developers, so that applications can only be offered for selected platforms for economic reasons.