On all models of iPad the speakers point to the side or slightly backwards, away from the screen. When you watch a movie or listen to music most of the sound will not reach your ears.
I built a simple sound reflector that redirects the sound forward. It's made from acrylic and I attached it with adhesive velcro so it's easy to attach to the iPad. Acrylic is cheap and can be quite easily bent using a butane burner.
The reflector improves treble and the overall volume. Less sound is sent to other parts of the room which is good if you have company that is not interested in hearing what you're listening to.
While bending the acrylic, clamp it between two pieces of wood and use another to bend it when you have heated it with the burner. Take care not to heat the acrylic to much because then it will be bubbly.