reactTag is simply a number that is used by react to identify view objects in your application . It is the result of findNodeHandle function, which takes a view reference as parameter.
Read moreWhat is Accessibilityinfo in react native?
Accessibilityinfo is an API provided by React Native to help you get the the current various statuses of the user device for both android and IOS . And track it as they change. Currently the Accessibilityinfo supports tracking the BoldText, Grayscale, InvertedColors, ReduceTransparency and ScreenReader.
Read more