Happens to be all the damn time.

http://www.urbandictionary.com/define.php?term=phantom%20vibration%20syndrome%20%28PVS%29

http://ehealthforum.com/health/topic14052.html

One smoke-filled evening I had all myself (as well as a couple friends) genuinely convinced that the phones were so good at tracking your movement/usage patterns, that they would vibrate when it thought it was in your pocket for no reason just to make you take it out and hence initiate casual conversation about the phone/phone company and it would be like free advertisement for them.

What do you suppose?

Aliens.

That's why I don't put my phone on vibrate anymore. It's all psychological and is prominent in those that are expecting a phone call or their work phone is their life line (to their boss). It usually starts after you miss a couple of important phone calls. After that, your brain triggers the sensation at the slightest move of the phone to help make sure you don't miss another important call.

The creepy thing is when that sensation always seems to be triggered before your phone actually rings. Happens to me all the time where I will feel it vibrating, pull it out of my pocket and find it wasn't really vibrating, then while I'm holding it, it will start vibrating because I'm getting a call or text.

i get that sometimes, feels like my phone is ringing in my pocket when its not even there.