iPhone 4S: Safe to update to 9.3.5?

[Uncle Wig]

I'm on iOS 8 something. Only issue is that my battery life is terrible. I did replace the battery awhile back, and it could just be a crappy battery. But it is said that 9.3.5 improves battery life a bit maybe?

Maybe not worth upgrading and I should look for a newer iPhone.

[p8712]

I'd replace the phone - ios 9 isn't great for the 4s

[rz]

I have two iPhone 4s's that are running on iOS 9. Why 2? Well, I wanted a cheap video camera that did 1080p recording. I got one of them for $20 off CL. The front was all cracked, but the phone itself and the camera worked fine. Then I got a second one on eBay with more drive space, but the back was all cracked. So I took them both apart, put the nice back on the nice front, and now have a good iPhone on which to record video. I wanted a video camera that I could take underwater (I found a great price on a housing for the 4s) that if it got destroyed, I wouldn't worry too much. I've mainly used it so far to record concerts and my son's school events.

The reason I went to iOS 9 is that there's a "feature" that allows you to record video in iOS9 without having the screen on. That kills the battery really quick. I was recording a play at my son's school last year and it died after about 80 minutes (the play was about 90 minutes long... I had to quickly get my 5s out to finish recording). Now, I can get a little over 2 hours, as long as I don't care about monitoring it on the screen. I'm hoping to use it at a concert in a few months.

[freeradical]

If you're running SL, you won't be able to sync your phone to your computer if you upgrade to iOS 9.

[JPK]

I just picked up a 4s to use as a dedicated music player in my car.
I am running 9.3.5 and have noticed no problems except the screen appears much smaller than my 6s!

JPK