Every mobile OS update has its bugs; that's why we often suggest you wait until the initial problems have been ironed out before upgrading. But it can be hard to wait, particular among Apple fans. And the company's new iPhones come pre-loaded with iOS 8, so there's no way to avoid it unless you also hold off on buying your new super-sized iDevice.

As a result, problems crop up, and one issue those with an iPhone 6 and iOS 8 noticed over the weekend was sluggish Wi-Fi.

"Wi-Fi problems on iPad Air, iPad mini with Retina display and iPhone 5S after upgrading to iOS 8," an Apple user wrote in a Saturday post on the Apple forums. "I am thinking about going back to my iPad 2 with iOS 7.1.2 that is working perfectly until the Wi-Fi issues are resolved."

"I bought iPhone 6 Plus today, and I also have the same problem," another user chimed in.

I also got an iPhone 6 on Friday, and noticed some sluggishness when connected to my home Wi-Fi network in New York. Twitter and Instagram photos took forever to appear, and opening a news story in Safari was hanging. I did a speed test using the Ookla app and got an abysmal 0.01 Mbps download and 1.05 Mbps upload. Minutes later, another test jumped up to 4.75 Mbps download and 0.24 upload, but a third test was again at 0.02 Mbps download and 0.76 upload.

Switching off Wi-Fi and running the test using AT&T's LTE network, however, returned 9.06 Mbps download and 3.55 upload speeds. A few minutes later, it was at 5.27 Mbps down and 2.36 Mbps up.

On my iPad 3 running iOS 7, there did not appear to be any issues, at least when it came to loading sites or refreshing my social feeds. An Ookla test on Wi-Fi got 5.30 Mbps download and 1.18 Mbps upload. Switching off Wi-Fi on the iPad, I got 3.42 Mbps down via AT&T and 0.74 up (the iPad does not get particularly good service on cellular in my apartment).

A few users on the Apple forums reported that navigating to Privacy > Location Services > System Services and disabling Wi-Fi Networking helped their Wi-Fi connections, but it's hard to tell if it worked on my device this morning since I'm on a much more robust enterprise Wi-Fi network here at PCMag.

Apple did not immediately respond to a request for comment.

Wi-Fi woes were not the only thing plaguing iOS 8 users. Others reported battery-drain issues. "My battery drains very fast (100 percent to zero in about 4 hours with minimal usage), started happening right after I upgraded to iOS 8. Issue started happening both on my iPhone 5S and on my iPad Air after iOS 8 upgrade," one user wrote.

My own iPhone 6 did not have any battery-drain issues, but a PCMag staffer here anecdotally reported that battery life on her new iPhone 6 was "not great."

Both of these issues have hit Apple devices in the past. In April 2010, Apple confirmed Wi-Fi problems with the original iPad. Two years later, Apple rolled out a fix for the Verizon iPhone 5 whereby the device was consuming data even when connected to Wi-Fi.

As for battery life, Apple in August offered new batteries for "a very small percentage of iPhone 5 devices" purchased between September 2012 and January 2013.

For more, see our list of 8 iPhone Battery Tips and Tricks.

Further Reading

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