When it comes to Apple, more people are loyal than not, in the sense they prefer to stick with Apple once they have owned an Apple product. This survey [via The Telegraph] of around 2000 iPhone users, for example, reiterates this claim further.
A couple of points to note from this survey are: what the reason behind this 'blind' loyalty to Apple is? and who owns what model of the iPhone at the time of this survey? For the first question, the top answer was because they were used to the iOS interface. And the second and third top answers were attributed to iPhone being the best smartphone (at the time of their purchase) and because their friends and family had an iPhone. Now I am not sure if the survey had an option of 'because of the ecosystem' in the list of answers for this question or not. Or what people meant as 'being used to the iOS interface' included the ecosystem as well, but I think another important reason for brand loyalty to Apple is the strength of its ecosystem. You just get hooked to it PERIOD.
Another interesting question in this survey was on what model of the iPhone they used and 81% of them said they still use an iPhone 5 or 4S or a 4. Only 10% have upgraded to the iPhone 5S! The post does suggests a "don't fix it unless its broken" attitude as a reason for this, but I think people are also waiting out for the iPhone 6 to come out. However I would have at least expected some of the 38% of people who still own an iPhone 4S or older model to have upgraded to an iPhone 5S.