There’s a new Apple iPhone accessory out called SoundClip which copies the effect of cupping your hand. SoundClip is made of plastic and snaps onto the base of the Apple iPhone around the speaker which creates a pocket and thus supposedly amplifies sound.
SoundClip for the Apple iPhone promises a 10dB increase in iPhone volume between 6kH and 20kHz, and when not connected to your Apple iPhone can be attached to the charging cord.
SoundClip for the iPhone costs $8.00, and well is way off being what could be termed an essential accessory, but it does stop you from covering the speaker with your fingers.
Source — gizmodo