While shopping at the dollar store, my daughter and I stumbled across one of these: a silicone iPhone amplifier. For a buck? She looked at me, I looked at her. She won. The little amplifier came home with us for a test run.
My tiny battery speaker set has been a subject of dispute between us. She borrows it; she blasts horrific music; she forgets to switch it off; she goes through batteries like a ravenous bear goes through a dumpster. We decided to see if a power-free US$1 amplifier would solve the problem.
You stick the phone into the unit -- it's a bit of a squeeze, and you can't use a bumper or a case with it. It
