The most popular phones of 2015 largely come from Apple's iPhone and Samsung's Galaxy lines, with the newest iPhone 6 and Galaxy S6 models topping the sales charts for their respective companies. The larger "phablet" iPhone 6s and Galaxy Note 4 are also popular choices, as are the older iPhone 5s and Galaxy S5 due to their lower prices and higher availability as compared to the newest models.
Both the Apple iPhone 6 and Samsung Galaxy S6 are very popular phones among consumers worldwide, with the iPhone remaining slightly more popular than the S6. However, shipments of Galaxy phones nearly matched that of Apple's phones as of summer 2015, suggesting that the two phones are very close in overall adoption. Both phones have similar form factors and have large high-resolution touch screens, but the iPhone runs Apple's proprietary iOS operating system while the Galaxy 6S uses Google's Linux-derived Android OS.
The so-called "phablet" category of cellphones incorporates phones that are larger than standard smart phones but slightly smaller than the smallest tablets. Samsung's Galaxy Note series of devices is considered one of the pioneers in this space, with the iPhone 6s Apple's attempt to capitalize on the phablet market. These phones are popular among users who run productivity apps on their phones, as the additional screen space can help make these programs easier to use efficiently.