Once you've bought an app, you cannot return it, as with non-internet stores. You must stick with the app you've bought.
Publishing your IPhone or IPad app on ITunes store is a multi-step process. You have two different choices. 1. Hire an expert like DotQ Solutions, LLC, or there are many others. 2. Do it yourself....
To sell apps on Apples App store you need to enroll on their developer program and then submit your app to Apple for approval. (See links below)
Download installous on iPhone (In the IPhone Store)
no one knows there are too many to count and there are always new one coming out and stuff