Make an iPhone dedicated application on the iPad to meet the requirements of Apple

My app is already It has been in the AppStore for a few months, and it always only works on the iPhone. I recently submitted a rejected update because the app is not running on the iPad. The exact reason for rejection is:

Reasons for Rejection:
2.10: iPhone apps must also run on iPad without modification, at iPhone resolution, and at 2X iPhone 3GS resolution

What do I need to do in Xcode to make my application run on an iPad in a small box with a 2X icon?

Any hint will be greatly appreciated…

Edit
This is my info.plist. This is my first application, I think I initially chose “Universal” choice. Is there an easy way to correct this problem?

First understand why your application does not work on the iPad. Most applications developed for the iPhone can work normally on the iPad (compatibility mode) , No need to modify; if you don’t have one, you must do something to prevent it. Do you rely on some hardware features? Make unfounded assumptions about the equipment you are running? How does your application fail when running on the iPad?

Once you figure out why it doesn’t work, you will be closer to solving the problem than you are now.