Because smartphones are PDA/cell phone combinations, they can receive and send phone calls; manage user information through their to-do list, calendar/organizer and notes; create or establish networks as well as synchronize data with the devices in the network; send and receive emails; and download and play media files. The operating system that most smartphones use is SymbianOS. This operating system enables the owners to use multiple applications at the same time. A user can check the phonebook in his or her smartphone while taking a call, receive a call while watching a video without interrupting the media player application, check the calendar or to-do list while composing an email. Moreover, smartphones can be synchronized with other devices like a personal computer or laptop to keep files updated. Third party applications enable the smartphones to support other systems such as Java, SyncML, Bluetooth and GPRS.
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