All of us have felt that excruciating embarrassment when your phone starts ringing at the most inappropriate moments.
Now Microsoft may have the answer to those occasions when you don't want to answer: smacking the face of your phone to tell it 'not now'.
The software giant has patented the idea, suggesting it will find its way onto Windows Mobile phones soon.
Microsoft's method is that, when your phone rings, it will turn on the 'accelerometer', which tells the phone which direction it is pointing in and can spot sudden movements.
When your phone starts ringing during the big presentation or the final part of the wedding vows, instead of scrambling for the 'off' switch or the volume button, you can simply smack the screen and silence your phone.
The patent was first spotted by patentbolt.com and, despite the wackiness of the 'whack' idea, it does solve a serious problem for phone users and one of the banes of modern life.
In January this year, orchestra music director Alan Gilbert was so appalled by the continuing distraction during one of the most poignant parts of a performance that he brought the musicians to a standstill.
A phone’s 'marimba' ring-tone went off from a front row seat of New York's Avery Fisher Hall during the final and most moving bars of Mahler's Ninth symphony.
In the patent, Microsoft said: 'There are a variety of circumstances under which it may be desirable to quickly control a device without having to interact with a traditional user interface.
'For example, often mobile device users forget to set their mobile devices in a silent or vibrate mode and the device rings or makes sounds at an inopportune moment.'
Microsoft say the whack could silence ringtones, an accidental button-press which turns the music on, an alarm or a text message sound.
Many other phone systems have a similar set-up. Some HTC and Samsung models can be silenced by turning the phone flat onto a desk in order to mute a distaction.
Source: Daily Mail