While I'm not sure FastCustomer's stat that the average person spends 60 hours waiting on hold annually is correct (though that could be because I've pretty much given up calling those numbers), there's no disputing how sorely-needed this app is.
It cleverly works by dialling the call center you require—for example, the AAA—and instead of you waiting on hold for the company, the app waits on hold instead. When the phone operator at AAA's call center is ready to take your call, the app instructs them to press a button to connect your call. The app then rings you back, and hey presto, you're ready to moan to the poor phone operator until they offer you a discount on your annual subscription. [iTunes]