There are so many smartphone speakers out there on the market right now, how do you know which one is right for you? Often the lowest tech option is the best, that's where this iPhone Booster comes in.
Using good old-fashioned know-how, someone took an old horn and modified it so that the speaker from the iPhone boosts itself through the instrument. Check out the video, it actually works really well!
Finally, an iPhone speaker for hipsters!