Device refresh rate

Users interact and see the results of how an application reacts and updates the image on the display of the device, which is why it's an essential part that provides an excellent user experience. Manufacturers continue to improve display hardware, so it's important to understand some display characteristics.

The refresh rate of a display is how many times per second the image on the screen can be refreshed. It's measured in hertz (Hz), so if the refresh rate of a display is 60 Hz, then the displayed picture cannot be updated more than 60 times per second.

The refresh rate that leads to a good experience depends on the purpose. Movies in movie theaters run at just 24 Hz, while the old TV standards were 50 Hz and 60 Hz. A typical monitor for a personal computer has a 60 Hz refresh rate, but the latest gaming displays can reach 240 Hz.

Since the device refresh rate is a hardware characteristic and a software developer can't influence it, the frame rate is of more interest. The following (from https://developer.apple.com/library/content/documentation/DeviceInformation/Reference/iOSDeviceCompatibility/Displays/Displays.html) shows the refresh rates and recommended frame rates for popular devices: