Running yiphone app on ipad

Hey everyone,

one of our projects got rejected from Apple because of the following reason:

"Also, we noticed that your app did not run at iPhone resolution when reviewed on iPad running iOS 8.3, which is a violation of the App Store Review Guidelines. We’ve attached screenshot(s) for your reference."

Within the manifest.xml I defined

<key>UIDeviceFamily</key>

<array>

  <string>1</string>

</array>

since the app is iphone-only. Has anyone a solution for this, since I did not find anything about it on the web.