M.E

This is a cool sound amplifier with high technology built into it.

Pros-

1. Gives you the sound as with professional audio equipment.
2. Easy to use. On and off button for smart operation. If it doesn't hear sound in 30 seconds, it will shutoff automatically, it will go live after hearing the sounds. Such a great feature to save battery life.
3. Great sound effect as if you are in a sound studio.
4. Is compatible with many apps and easy to use.

Cons-
There are other similar products too like UE Boom.