Q: new update put my iphone 4s into a loop

Hey Twdaniel1,

Sorry to hear about your troubles upgrading to the latest version of iOS 9 on your iPhone 4s. Let's see if we can get that sorted out. 

I will start out by saying that you will need to restore your iPhone to get it passed that screen. I would first take a look at the first article below and make sure that you have a backup in place in either iTunes or iCloud. Once you do that you can restore your iPhone and after that completes, you can put your backup back on your iPhone to get you back up and running. 

If your iOS 9 device is stuck on Slide to Upgrade
https://support.apple.com/en-us/HT205239

If you are having issues with restoring your iPhone, you can put it into recovery mode and iTunes will prompt you to restore. Those details are outlined in the article below. 

If you can't update or restore your iPhone, iPad, or iPod touch
https://support.apple.com/en-us/HT201263​

Take it easy