Absolutely irresponsible behaviour by passengers. There are audio announcements informing trains arriving/departing with name, source, destination and the platform number blaring at stations. Coach indicators display train number and coach numbers on platform. If these passengers can't see/hear them, it is only sensible to ask others whether the train is going to their destination before boarding. All these smart phone users should show a little smartness -- ouch, a little sense would be enough, they wouldn't board wrong trains.