I'm finishing off the last details of a website that helps add push to any app (and manages all server aspects). Once set up, you can broadcast a message to all customers who have your app. You could, for instance, tell all those who own the lite version that the full version is on sale. And, in push style, their phone will buzz and your message will be front and center. The only part of the site that is not finished is the front page (.. looks, not as nice as I'd like). Otherwise, the push functionality is 100% working, and I'd love feedback/suggestions. http://www.iphonepusher.com For now, it's 100% free. Eventually I'm thinking I will work in some sort of impressions based advertising fees. Any thoughts?