There is a pretty simple answer for your vibrations. It's known as Phantom Vibration Syndrome. Your brain subconsciously expects your phone to vibrate from phone calls and messages, and sometimes makes you think the phone is vibrating even though it never does. Have you ever seen the phone vibrate randomly without a call or msg while the phone was sitting on a table or something? Probably not. I know that I've personally experienced these weird vibrations dozens of times myself.
Check out this link to USA Today
http://www.usatoday.com/news/health/2007-06-12-cellphones_N.htm
I fully understand this concept because it happens to me a lot. BUT, my 3GS was just sitting on my desk not plugged in, and it vibrated. When I checked it, there was no new message anywhere. It does happen several times a day with no explanation.
At first I thought it was just me but my phone will randomly vibrate, like as if I just got a text message but when I check my phone it will have no new notifications. It has been happening about 3 times a day and at first I thought it was just me but I'm sure it isn't at this point. My phone is always on vibrate so I don't know if it does the same when it isnt. Has this happened to anyone else?
i have a very similar problem with my one year old 3gs. this just started happening within 2 days of this and i have never had anythng wrong with my iphone before. so what is happening is that when the iphone's vibrate switch is on (you can see the red dot and it is muted) it does the normal vibrate once to let you know that it is on mute. but with the slightest movement of the switch it will switch really really fast between muted and un muted. showing the icon on the screen and vibrating. when this happens the switch is only moved about one milimeter and is not nearly colse enough to switch back to the unmuted mode. there is no dirt in the switch and everything else is fine. but this happens constantly when it is in my pocket or wherever it moves even a little bit. if anybody has a fix for this it would be much appriceated.
My iPhone 4 does this randomly. I will be sitting across the room, hear it vibrate and see it light up, yet I have no emails, messages, notifications, etc.
Hi,
I noticed this on my new iPhone 4S 16GB. I was a little confused at first as like you said there were no indications of any messages. Found out it was the sub folders from my secondary work email that were causing the alert. No red circle in the top right of the email icon appeared whichshould look into.
Hope this helps!
p.s. My work email runs through the Microsoft Exchange.
I had the same problem and it was driving me crazy. On closer inspection of the switch, I noticed some dirt and lint build up between the switch and the iPhone case. After thoroughly cleaning this out, the random vibrating stopped. The switch is still sensitive in the off position but it only vibrates when pressure is applied.