The refresh rate is the measure how the smartphones display are being updated. In other words, we can say how quickly the content on the screen is being refreshed every second. The unit of measurement is denoted as Hertz ( HZ) and is the indication of number of times where the display undergoes refreshing every second. A 60 HZ display means that it would refresh 60 times per second where as 120 HZ would signify that it is capable of displaying refresh 120 times per second.
If the updating time is fast, it is the reflection of lower latency since pixels are subjected to refreshing very frequently. However, the refresh rate is not only the chief factor in displaying the latency but it can influence a lot.
It is not necessary that the smartphone would take up refreshing immediately in each cycle rather each horizontal row of pixels would continue to refresh until the entire display updates at the desired rate.
A higher touch sample rate is the reflection of less lag between input and action and this is more relevant for the fast paced games.
While choosing a brand smartphone, display of refresh is not the special feature but other factors such as contrast, quality of screen of the smartphone, white temperature, colour gamut are also taken into considerations.