FullStory recording automatically enters an idle mode if it does not detect any user input for several seconds. In this mode, it scans the UI less frequently to conserve power and bandwidth.
FS.resetIdleTimer() forces the FullStory SDK out of idle mode, and prevents it from entering idle mode until another several seconds have passed.
Most apps do not need to use this function, because FullStory automatically detects most user interaction (such as touch or keyboard input) and will not enter or stay in idle mode while the user is active. However, if user input comes in a form that FullStory can't detect (such as a notification from a third-party app), you can call
FS.resetIdleTimer() to ensure that the interaction is recorded.