I have a free version of my app Nag-O-Matic now available in the App Store. It features fewer nags than the pay version and is ad supported but works 100% well
itms://itunes.apple.com/us/app/nag-o-matic-lite/id348784393?mt=8
itms://itunes.apple.com/us/app/nag-o-matic-lite/id348784393?mt=8