You can convert iPhone xib to iPad xib using the next step.
( xcode) Open As > Source Code
:
<archive type="com.apple.InterfaceBuilder3.CocoaTouch.XIB" version="7.10">
Replace with:
<archive type="com.apple.InterfaceBuilder3.CocoaTouch.iPad.XIB" version="7.10">
"IBCocoaTouchFramework" "IBIPadFramework"
> Builder - iOS
al xib... iPhone xib iPad xib.
, .