Apple's iOS.
Crittercism, a mobile app monitoring company, released data on crash reports from Dec. 1, 2011 through Dec. 15, 2011, that shows iOS crashes much more frequently than Android -- by a 2-to-1 margin, to be specific. The biggest offender is iOS 5.0.1, which accounted for 28.64 percent of all crashes, PCWorld reported, and the most crash-prone Android operating system is 2.3.3, accounting for 3.86 percent of crashes.
