Mobile accessory speakers are offered in a range of sizes, from docks many times larger than the average smartphone to tiny systems that deliver a surprising amount of sound from outputs no larger than a coin.

One of the newest products on the market is the Pocket Boom speaker. This device, which is smaller than the typical phone and literally fits into a pocket, creates sound by sending vibrations into whatever it's placed on.

The technology isn't revolutionary. Anyone with close neighbors knows that speakers placed against a wall, floor or ceiling can result in unwanted reverberations and a knock on the door, and well-placed sound equipment often means strategically using the features of the room to amplify and control vibrations and waves.

Nevertheless, the Pocket Boom is a novel concept due to its size and marketing for mobile devices. By adhering a sticky pad to a surface – preferably a smooth one with a hollow core underneath, such as a box – the device relies on its placement and the amplifying capabilities of the hosting item to produce a much better sound quality than many equally sized (and priced) miniature MP3 speaker systems.