Bottom line: Yes, you should upgrade to iOS 9<article>
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<p>“Should I upgrade to iOS 9?” is the question I hear the most around launches like this, even more than, “Should I buy a new iPhone?” People generally know if they want the new hardware, but whether or not to put a new OS on a device they already own seems like more of a gamble.</p><p>I’m here to tell you: iOS 9 is a pretty safe bet.</p><p>First of all, it runs on every device iOS 8 runs on, going all the way back to the iPhone 4s. (And when I
find the iPhone 4s I bought back in 2011, and was in service as my husband’s phone from 2012 through 2014, I’ll thoroughly test it and let you know if iOS 9 is usable on the thing.) Since iOS 9 has been in beta, we’ve tested it on a few devices, including iPhone 5s, iPhone 6,
the third-gen iPad, an iPad Air, an iPad Air 2, and an iPad mini 3. The beta versions have been extremely stable, and none of the hardware we’ve used it on became sluggish or felt hampered by the new OS.</p><p class="jumpTag"><a href="/article/2984347/ios/bottom-line-yes-you-should-upgrade-to-ios-9.html#jump">To read this article in full or to leave a comment, please click here[/url]</p></section></article>
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Bottom line: Yes, you should upgrade to iOS 9