Android is more reliable than iOS as an operating system as per a report by Blancco Technology Group (BTG). The report further adds, Apple devices such as iPhones and iPads suffered bigger failure rates than Android in Q3 2016.
Note that here ‘failure’ is termed as any bugs, crashes, connection difficulties, overheating etc. 
BTG’s report claims that about 62% of iOS devices suffered from failures as compared to 47% Android based devices in the third quarter of 2016.
Among Apple devices, iPhone 6 reported a failure rate of 13% making it the most less reliable Apple device. Next was iPhone 5S and iPhone 6S with 9% of failure rate each.
Commenting about the overheating issue, the report said, “If an iOS device exceeds a certain internal temperature threshold, it could have a ripple effect on other aspects of the device’s performance.”
“For example, overheating could lead to the device no longer charging. It could also cause the display screen to dim or go black altogether. Other residual effects could be a weakened carrier signal or the camera flash being disabled temporarily,” it added.
Meanwhile, in the Android community, Samsung displayed the highest 11% failure rate. Among the problems faced by Android users, USB problems and battery drain topped the list.
And for the most unstable app, Pokemon Go took the award with the App crashing about 5% of the time.