I have an iPhone 4S with 6.1.2 OS. Here's the problem: In either sound/vibrate or silent mode, phone doesn't vibrate when calls come in. It does vibrate on incoming text messages and other notifications in either mode. Any suggestions? I have tried a soft restart.
I know the Vibrate feature is important on your iPhone 4S, and I would be frustrated if I was unable to use it myself. Let's see what we can do here. Try this: From the Main screen, select Settings> Sounds> Vibrate on Ring & Vibrate on Silent ON. Then restart phone. Please keep us posted and let us know if this helps.
I have tried that before, but tried again and still the same results. Any other suggestions? This is actually my sons phone and it's frustrating when he's not alerted to my phone calls, especially since his phone is usually on silent.