I suppose you use a custom cell that has a label for displaying the date. A pseudo code for cellForRowAtIndex
would be:
Item *aItem = [_stagesPerMonth objectAtIndex:indexPath.row];
NSDate thisDate = aItem.date;
// Obtain the date of the previous event or nil if this is the first event
NSDate prevDate = indexPath.row > 0 ? _stagesPeMonth[indexPath.row - 1].date : nil;
// Date label is hidden if the previous date is the same as this.
dateLabel.hidden = [thisDate isEqualToDate: prevDate];
The syntax may be different in your case.