iOS 8 on the iPhone 4S: Performance isn't the (only) problem

New OS wants screen space and processing power that the old phone doesn't have.

Why can't the iPhone 4 run iOS 8/9/10? - Quora

Apple iPhone 4S Review

Apple iPhone 4S: What's In It For You vs iPhone 4? - Page 5

Apple fixes iPhone battery issues

iOS 8.2 iPhone 4s Reviews: Should You Install iOS 8.2?

discussion] hello. i downgraded my iphone 4s to ios 9 to ios 6. works , facebook. but the messenger doesn't work, it's hard to fix. I also installed other tweaks, but the

iOS 8: 35 Problems and Bugs and How to Fix Them

How to Unlock iPhone 4/4s and Use It With Any Carrier in 2024

Don't Buy the BS: iOS 8 Works Just Fine on iPhone 4S « iOS & iPhone :: Gadget Hacks

Apple iPhone 4S review

A few notes on the iPhone 4S

iPhone 4S owners file suit against Apple, claim iOS 9 made phones unbearably slow : r/technology

If you have an iPhone 4s, you might want to hold back on iOS 8 - 9to5Mac