A mobile phone, known as a cell phone in North America, is a portable telephone that can make and receive calls over a radio frequency link while the user is moving within a telephone service area.
A personal digital assistant (PDA), also known as a handheld PC, is a variety mobile device which functions as a personal information manager.
A Pocket PC (P/PC, PPC), also known by Microsoft as a 'Windows Mobile Classic device', is a kind of personal digital assistant (PDA) that runs the Windows Mobile operating system.
Siemens AG is a German conglomerate company headquartered in Berlin and Munich and the largest industrial manufacturing company in Europe with branch offices abroad.
Siemens Mobile was a mobile phone manufacturer and a division of Siemens AG.
A smartphone is a handheld personal computer with a mobile operating system and an integrated mobile broadband cellular network connection for voice, SMS, and Internet data communication; most, if not all, smartphones also support Wi-Fi.