Confusing about create an app which has version for both iphone and iPad

Question

I am creating an app which has version for both iPhone and iPad, iPad version has different GUI and some more functionality. Currently, I separate them in 2 projects.

After reading this article: Jump from iphone to ipad development...

And see: "All iPad users who have already downloaded your free or paid App to their iPhone or iPod Touch will be able to download your iPhone App – only if you have updated your binary submission to the App store to make your iPhone App compatible with iPad. If you do not update and create the separate binaries, then you are potentially losing out. Using the new SDK you will be able to create a single binary which will install one version of your app when used on the iPhone or iPod Touch and a different binary when installed on an iPad"

I don't know if my current way is correct when separate them in 2 different apps! and how to create single binary which will install one version of your app when used on the iPhone or iPod Touch and a different binary when installed on an iPad?

Does anyone know about this please help me!

Answer 1

There are two ways to have an app on both iPhone and iPad. One is to build two separate apps that do the same thing. This is what you are doing, but not what you described. It creates two applications, one for iPhone and one for iPad, that do the same thing. As such, purchasing one will not give the user access to the other.

If you want the user to be able to use a single app on both the iPhone and iPad with different interfaces, you need to build a universal app. It will contain code and resources for both the iPhone and iPad. See iOS Application Programming Guide: Build-Time Configuration Details. About two thirds of the way down is a section on universal applications.

Edit: I found another document specifically about universal applications: http://devimages.apple.com/iphone/resources/introductiontouniversalapps.pdf

Answer 2

Whether to have two separate SKUs on the App Store or not is usually more of a business question than a technical one. Separate apps lets you segment your users and charge more for the iPad version. On the other hand a universal app is usually better received by users and can make the most sense if what you have is a premium, 'expensive' niche app.

If you want to go the universal route:

If you have an iPhone application that you want to upgrade to run on iPad devices you need to upgrade the target that builds your iPhone application into a target that can build both an iPhone and an iPad application, or add a target to your project for building the iPad application.

To upgrade an iPhone target for iPad development, select the target in the Groups & Files list and choose Project / Upgrade Current Target for iPad.