Apple's iOS devices like iPhones and iPads crashed twice as often in the second quarter compared to the previous one, new data shows.
Fifty-eight percent of iOS-based devices suffered from "performance failures" like apps crashing or components shutting down during the second quarter, up from 25% in the first quarter, according to a study by mobile technology service provider Blancco Technology Group (BTG).
For the first time ever, Apple's iOS performance failure rate was higher than Google's (googl) Android. Thirty-five percent of devices running Android had problems during the three months ended June 30, an improvement from a 44% failure rate in the preceding quarter.
Apple did not respond to a request for comment.
BTG came up with its findings by monitoring the company's SmartChk, a service that runs tests on smartphones and tablets to find problems. That information can then be used to repair the devices. BTG didn't say exactly how many iOS- and Android-based devices were analyzed in its most recent study, but a spokeswoman confirmed that it analyzed "millions of devices from North America, Europe, and Asia."
The data provides some important insight into why mobile apps crash and the likely causes.
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For instance, on iOS devices, the most common "performance failure"—about two-thirds of the total—was an app that crashed and forced users to reopen it. The company also found that 11% Apple device owners experienced problems with Wi-Fi connectivity.
On the Android side, the camera was the most likely source of trouble, accounting for 10% of performance problems. Another 10% were attributed to battery charging while 7% were blamed on touchscreen performance.
In its study, BTG revealed that iOS troubles were likely due to Apple's iOS 9.3.1 update in March followed by its 9.3.2 update in May. They both caused problems with "battery drain, random crashes," and other unidentified problems, the company said.
Indeed, not long after the iOS 9.3.1 update earlier this year, customers complained that it caused bugs and glitches that could render their devices useless. Although Apple fixed the issue in iOS 9.3.2, the update included other bugs, leading to yet more problems. Apple's latest iOS version is 9.3.5, which, at least right now, is believed to be more stable than those before it this year because it has fixes for bugs those operating systems had.
It was a similar story on the Android side, which also experienced problems due to Android software updates, BTG said.
BTG then turned its attention to the apps themselves to see which first- and third-party programs caused mobile devices to crash. It found that half of the apps running on iOS devices last quarter crashed, compared to 23% of those running on Android.
However, Apple's (aapl) apps appeared to be far more stable than those from Google. In fact, the Google Play app marketplace was most likely to crash in the previous quarter followed by Google Contacts Sync, which syncs user content on Android, BTG found. Android's built-in Address Book and Photos app also played a big role.
Third-party apps proved to be the biggest soft spots on iOS. BTG reported that photo-and-video-sharing app Snapchat was the most-likely app to crash on iOS followed by Facebook-owned photo-sharing app Instagram, Facebook (fb) itself, and Facebook's mobile-messaging service Messenger.
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One other tidbit from the BTG findings: Samsung smartphones were the most likely to crash on the Android side with a 26% failure rate.