Smartphone images are often shaken because the user is forced to hold the smartphone with one hand and press the on-screen imaging button with the index finger of the other hand, but there is another way that allows him to shoot with the smartphone quickly and easily.
This method is to use the volume control buttons as an imaging button on Apple iPhone starting from iOS 5 and Google Android starting from 4.3, so the user can hold the smartphone with both hands and get still and clear images.
There is no difference between pressing the "Volume Up" button or the "Volume Down" button, where images are taken when either is pressed, this function is often effective by default, and if not the user can see the settings Camera application and activated.