While endorsing the points raised by gentleman, let me higlight another dimension of the said subject. With the latest window releases by Microsoft, there are prospects that in the future, one version of the operating system may work in PCs, laptops, tablets and smartphones. This is indeed what many smartphone makers are to plan and then come up with appropriate solutions.

Another important thing is the trend of applications and their selection. Like, many smartphones prefer Skype which is one of the most compatible app for IOS, Android and Java. However, some other apps that are based on some particualr Os may also be needed to managed. See, Vonage mobile, or Axvoice apps for the smartphones may be a choice for the customers. Hence, open source OS and third party apps dimensions are also needed to be kept in mind.