I received an email today from ING Direct Sharebuilder incenting me to download their mobile app.
The deal works like this: Download ShareBuilder's mobile app for iPhone®, BlackBerry® or Android™ then make a trade using the app between today and October 28. Once you execute the trade you'll receive a rebate to offset the cost of the trade in an amount to make the cost 5 bucks. It's a 1 trade deal per account.
The question you have to ask yourself is what price you'd charge them for you to download and set up their app. For me, it's probably not worth it. I just don't trade in the account since I bought stocks for my son.