Are iPad and iPhone versions of an application upgraded independently or as one binary?

We have an app (runs on iOS 3.0 or later) in app store already and , we planned to upgrade that app as an universal app.

I believe that, when we submit an universal app ( runs on iOS 3.2 or later) , App store retains a copy of iPhone-only version of that app , and serves that copy to iOS 3.0 Customers (if OS Deployment target in Universal app is set to iOS 3.0).

(Ref: https://devforums.apple.com/message/297572

Correct me if I have misunderstood that.开发者_如何学编程)

After submitting my Universal app , can I update my iPhone-only version without affecting Universal app?

Simply, Can I address any feature requests of iOS 3.0 user (or) can I edit the retained copy, after upgrading my app as an Universal app?

There are two ways you can go when it comes to deploying an application for iPad and iPhone. The first is to create two different applications with the same name, one for the iPad and one for the iPhone. This approach lets you independently update the two versions, as well as make people pay for each version.

The second way is to create a universal iPhone / iPad application that consists of a single binary which alters its function and interface depending on which device it is running on. When you update this application, it is updated for both platforms at once. This is the approach Apple recommends, because it simplifies the user experience. If a user buys or downloads your application, it will transparently work on all of their devices. They only pay once for it.

If you upgrade your existing iPhone application to an iPhone / iPad universal one, the universal one replaces the previous iPhone-only version on the store, just like every update you do replaces the previous version.

I prefer creating universal versions, and it is what I've done for my applications. However, I can see why people would want to create separate versions of their applications if the iPad version is vastly different than the iPhone one (see OmniFocus as an example of this) and they want users to pay for the effort in creating the new application.