84% of iPhone users say that they are loyal to the brand

"Apple is well ahead of rivals in building brand loyalty among its users in a mobile market where the key brands are rushing to build as large a foothold as possible, a study by research firm GfK showed.
Some 84 percent of iPhone users said they would pick iPhone also when they replace their cellphone, while 60 percent of consumers who use smartphones running Google's Android said they would stick with phones using the same software.
Only 48 percent of people using Research In Motion's cellphones said they would stay loyal to their Blackberrys, the study showed.
More than 70 percent of consumers said they would stick with their phones due to their seamless integration of features and access to content."

Source:  Research by GfK, reported by Reuters, 25th November 2011

Methodology:  "The research firm interviewed around 4,500 people in Britain, France, Germany, Italy, Spain, Brazil, China, the United States and Japan."