Pocket dialing

Pocket dialing (also known as pocket calling or butt dialing) refers to the accidental placement of a phone call while a person's mobile phone or cordless phone is in the owner's pocket or handbag. The recipient of the call typically hears random background noise when answering the phone. If the caller remains unaware, the recipient will sometimes overhear whatever is happening in the caller's vicinity. A pocket-dialed call can continue for many minutes, or until the recipient's voice mail system ends the call.

The phrase "pocket dial" was added to the Oxford English Dictionary in August 2015.

Modern cellphones come in three configurations: "flip" phones, where the phone is physically closed rendering the keys inaccessible, touch phones where a finger or stylus is required to use the controls, and open phones, where keys or buttons are always exposed. Pocket dialing primarily occurs with touch phones and open phones.

Typically, a call is caused by the person's movement changing the shape of the pocket in a person's clothing in such a way that a small amount of pressure is applied to some of the buttons, or in the case of a touch screen phone, a call can also be caused by the screen of the phone facing the person's body and a small amount of perspiration creating sufficient conduction through their clothing such that the capacitive touch screen detects their clothing as if it were a touch from the user's finger.

The keypad lock feature found on most mobile phones is intended to help prevent accidental dialing, but is often so trivial that the keypad is easily pocket-unlocked. Sometimes the unlock sequence requires nothing more than pressing a button and then applying a random swiping motion to the screen, or in the case of some keypad phones, it sometimes requires nothing more than holding a particular key for several seconds. To make matters worse, most phones respond to more complex lock settings, such as requiring a passcode to unlock the phone, by making the pocket dialing of emergency services even easier. On most keypad phones, one can dial emergency services simply by ignoring the fact that the phone is locked, dialing the number, and pressing "send." On touch screen phones, passcode screens often include a single button that, when touched for just a few seconds, will dial emergency services. The result is that it is often preferable to disable the passcode, since while doing so increases the likelihood of pocket dialing family and friends, it decreases the likelihood of pocket dialing emergency services, which is preferable as the consequences of pocket dialing emergency services are usually much more severe.

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Wikipedia