Here is a handy little thing for your iPad, it is a clip on device and has no moving or electrical parts, which makes it very interesting and as there is nothing to break, it is very practical in all sorts of situations.
These are the specs for the snap on speaker for the Apple iPad;
For IPad 2/3 electronic sound amplification device for loudspeaker pink
Amplifiear Electricity-Free Snap-On Speaker Design for iPads Boost The Volume pink
Amplifiear is a simple analog amplifier for the iPads external speaker.
It snaps on to the iPad, bouncing sound from the rearward-facing speaker back toward the user.
The Amplifiear is a sound amplification device for the new iPad
This handy little device will set you back around £7 ($12) from Amazon