We have featured several nice passive amplifiers for iPad, but if you use iPhone 5, no doubt the following iPlifier sound amplifier will be more suitable for you.
iPlifier is a simple yet practical sound amplifier designed for iPhone 5. As we can see from the images, the sound amplifier features ultra compact and easy-to-use design, all you need to do is to connect the sound amplifier with the Lightning port of your iPhone 5 in order that the custom designed channel is able to redirect the sound towards you, amplifying it and enhancing your listening experience of music, videos and games, moreover, the sound amplifier works well with iPhone 5 with or without a protective case, apart from that, when not in use you can also easily attach it to your keychain for easy carrying.
At present the inventor of iPlifier is raising fund at Kickstarter. Pledging $8 will let you own the iPhone 5 sound amplifier with a clasp. If you’re interested, jump to Kickstarter official site for more details or check out the following two demo videos first.