Is it mandatory to use it? Or the moderators will calculate it them selfs?
Because i just did a new run in gta sa android version (desert speedrun) and i tried to follow the rules of timing but its a little bit hard, should we start the timer when we press the first skip hutton or wait until the cutscene start? Do we stop the timer when we finish the flight mission or wait until the mission passed pop up? So ineed help i think i got 28:29:697 in this speedrun putting me in the second position

Sorry for my bad english im still learning :)

You start the timer in the same moment you skip the cutscene. You stop the timer at the first frame of mission passed screen.