Multiscreen Development

Because the pixel density of screens varies considerably from device to device, the pixel is not a useful unit of measurement for specifying the layout of apps. Instead, the appropriate unit of measurement is the "point" (pt) for IOS and "device independent pixel" (dp) for Android.

 

Unless otherwise stated measurements used in this guide are in points.

 

1 pt is approximately 1.1 dp

 

Apple User Interface Guidelines

Android User Interface Guidelines