Interesting! Thank you for pointing this out. I'll test out the problem and report it to our lead developer. I'm glad you found a way to fix it for your app!

Hi Pablo,
The default page corners should still be working. And objects in the corners actually shouldn't affect them, because the page turn area is in front of all other elements. When you preview the app, are you selecting multiple pages to preview, not only the current page? In each page's "Features" tab, do you have "disable page flip backwards" and "disable page flip forwards" set to "no?"

Hi there,

InteractBuilder 4 is actually available not through the iOS store but through the interactbuilder.com website. Here is a description of how to download the software: Download InteractBuilder.

Hi Sean,

If you want to use one app for different marketplaces, it will automatically resize proportionally to fit within the different screen sizes, with a little black space around whichever dimension is larger. If you do prefer to create different versions of the app, you can duplicate the app, change the dimensions, and adjust the artwork to apply to different screen sizes. This decision is up to you : )

Regarding the app icon, as long as the icon you included in your app publishing materials is a 1024x1024 square without rounded corners, the icon will be adjusted (size and rounded corners radius) for each marketplace. The following user guide article describes this as well as other publishing options: Publishing to the App Marketplaces.