If your iPhone 4s is acting up or just doesn’t seem to be holding its charge as well as it used to, a hard reset may be the solution. Here’s how to do it:

  1. Turn off your iPhone 4s.
  2. Hold down the Sleep/Wake button and the Home button at the same time until you see an Apple logo appear.
  3. Release both buttons and wait for your iPhone 4s to restart. ..