How to add Event in device Calender.

        EKEventStore *eventStore = [[EKEventStore alloc] init];

        

        EKEvent *event  = [EKEvent eventWithEventStore:eventStore];

        event.title     = @"My Event Name";

     

        event.startDate =[NSDate date];

        event.endDate   = [[NSDate alloc] initWithTimeInterval:60 sinceDate:event.startDate];

       

        [event setCalendar:[eventStore defaultCalendarForNewEvents]];

        NSError *err;

        [eventStore saveEvent:event span:EKSpanThisEvent error:&err];  

And don't forget to add #import  to your file and EventKit framework to your project.