With Microsoft being in pre-Windows-Phone-7 release limbo, and RIM being on a slow losing streak for quite a while now, it's not surprising that Android is gaining market share on these mobile platforms. But Apple started selling its iPhone 4 late in June, and the bump caused by the new device on the market was not enough to start catching up with Android.
Why is Apple losing ground? For the most part, analysts agree that Apple's sales have been hurt by the lack of contracts with some of the world's largest mobile carriers, such as Vodafone and Verizon. Apple should seriously consider changing this if it wants its iOS to stay ahead of Android.
Still, it's important to look at this data in perspective. With the smartphone market constantly growing (according to comScore, it grew 11% from April to July), both Apple's iOS and Android were actually on the rise -- Android was simply growing faster. Furthermore, iPhone 4 was available only in the last month covered by this comScore report. In the next couple of months, we may get a clearer picture of the smartphone market.