During the initial device emulation (that is, Emulate Performance is not checked), the Emulator tab runs with full desktop or laptop speed. To accurately emulate device performance, calibrate each device on the Emulator tab.

To calibrate the device, the Emulator tab runs a test application and compares the test result with the result stored in the database, which was obtained by running the same test application on the actual device. Device Central derives an index number based on the comparison. This enables Device Central to know how much to slow down the desktop or laptop computer to emulate the device. It also gives Device Central a way to group devices into Performance Index categories. The categories let you compare device performance (i.e., a high index number indicates a high-performing device). Player version, display size, heap size, monitor size, and the computer's memory consumption all affect the calibration result.

Most of the Performance options, except for Rendering and Calibrate, remain disabled for any device that is not calibrated. After you perform the first calibration for a device, all performance options are enabled for that device.

To achieve accurate emulation results, perform device calibration frequently because other processes running on your computer affect performance.