Bone Horn Stand works same like old-fashioned horn-speakers on gramophones to increase the sound. It’s a silicon case that fits over the iPhone’s bottom, and when the sound passes through trumpet shaped tube it increase the sound of iPhone to 12 decibels. The Bone Horn Speaker also works as a stand, supporting the iPhone in horizontal or vertical orientation, and even has a nubbin that will pass your presses on to the home-button beneath. Unfortunately, this amplifier matches only on the iPhone 4.