Turn your mobile into a Microphone!
Use it to eavesdrop record sing and announce.

Eavesdrip Mode (aka SUPER HEARING): Connect your headphone turn on live mode and place your phone in the nearest position possible to catch every single tiny conversation.

General mode instructions: Connect your phone to a large speaker or headphones and use your smart phone as a live microphone.

Note: Make sure you are far from the speaker and use echo-protection mode to avoid Echo-loop