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http://tinyurl.com/pvhzbhq

Several phone series have been introduced to address specific market segments, such as the RIM BlackBerry focusing on enterprise/corporate customer email needs; the Sony-Ericsson ‘Walkman’ series of music/phones and ‘Cyber-shot’ series of camera/phones; the Nokia Nseries of multimedia phones, the Palm Pre the HTC Dream and the Apple iPhone

Resource: https://en.wikipedia.org/wiki/Mobile_phone