That is the question for iPhone 4S owners, and opinions differ on whether it can properly handle the load of iOS 8:
So yes, it’s entirely possible for you to download the brand new iOS on your brand-old iPhone. And by doing so you’ll get a lot of goodies like more keyboard options (finally) and fun widgets. Ars ultimately concludes that it’s a trade-off you should go ahead and make.
But to us, cramming that shiny new software into the 4S’s cozy yet slightly musty house is a tight fit that will leave phone and user alike groaning. New features like widgets and alternate keyboards are nice, but not at the cost of so much screen space and speed.
Another report shows however that the increased load times aren’t exactly intolerable, with the worst offender (Safari) jumping from 1.25 seconds to 2.16 seconds. The other apps tested measured increases of just small fractions of a second — and the inevitable 8.01 or 8.1 update might tweak those times down a bit.
My boys, ages 4 and 8, are plenty happy running iOS 7 on Melissa and my old 4S phones, but I’m curious to see how well the new iOS really does work. It’s a risk though, since you can’t roll back to the previous version.
So I’m going to be a naughty dad and install iOS 8 on the younger boy’s phone and hope he doesn’t notice if it sucks. He doesn’t use it much, anyway, preferring the big screen on my ancient iPad 1. I’ll report the results back to you in the next few days.