How to make 3D objects compatible with retina display?

I’m making a game for iOS platform which is compatible with retina display. Whenever I run the game on my iPad mini with Retina Display (iPad Mini 2), the objects are blur and not sharp. How to make them work on retina display?

You need to set the display resolution to “native” to get retina on an iOS device. If you have that set but still objects are blurry, it may be the objects themselves. Are they sprites?