You can use the instant manual run feature on the Home page to turn on and off the zones instantly. The blue play button is for instant manual run for your zones. You can tap the "05:00" time value to change the watering duration to 1 minute.
Tap the blue button and there will be a pop up window. When the zone is being watered, the zone area will become blue and watering duration is shown in the lower left corner of the zone area. Tap the red square to stop watering.