which object was tapped?

I'm new to gesture recognizers so maybe this question sounds silly: I'm assigning tap gesture recognizers to a bunch of UIViews. In the method is it possible to find out which of them was tapped somehow or do I need to find it out using the point that was tapped on screen?

for (NSUInteger i=0; i<42; i++) {
        float xMultiplier=(i)%6;
        float yMultiplier= (i)/6;
        float xPos=xMultiplier*imageWidth;
        float yPos=1+UA_TOP_WHITE+UA_TOP_BAR_HEIGHT+yMultiplier*imageHeight;
        UIView *greyRect=[[UIView alloc]initWithFrame:CGRectMake(xPos, yPos, imageWidth, imageHeight)];
        [greyRect setBackgroundColor:UA_NAV_CTRL_COLOR];

        greyRect.layer.borderColor=[UA_NAV_BAR_COLOR CGColor];
        greyRect.layer.borderWidth=1.0f;
        greyRect.userInteractionEnabled=YES;
        [greyGridArray addObject:greyRect];
        [self.view addSubview:greyRect];
        NSLog(@"greyGrid: %i: %@", i, greyRect);

        //make them touchable
        UITapGestureRecognizer *letterTapRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(highlightLetter)];
        letterTapRecognizer.numberOfTapsRequired = 1;
        [greyRect addGestureRecognizer:letterTapRecognizer];
    }

Define your target selector( highlightLetter: ) with argument as

UITapGestureRecognizer *letterTapRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(highlightLetter:)];

Then you can get view by

- (void)highlightLetter:(UITapGestureRecognizer*)sender {
     UIView *view = sender.view; 
     NSLog(@"%d", view.tag);//By tag, you can find out where you had tapped. 
}

Its been a year asking this question but still for someone.

While declaring the UITapGestureRecognizer on particular view assign the tag as

UITapGestureRecognizer *tapRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(gestureHandlerMethod:)];
[yourGestureEnableView addGestureRecognizer:tapRecognizer];
yourGestureEnableView.tag=2;

and in your handler do like this

-(void)gestureHandlerMethod:(UITapGestureRecognizer*)sender {
{
    if(sender.view.tag==2) {
        //do something here
    }
}

Here is an update for Swift 3 and an addition to Mani's answer. I would suggest using sender.view in combination with tagging UIViews (or other elements, depending on what you are trying to track) for a somewhat more "advanced" approach.

    let yourTapEvent = UITapGestureRecognizer(target: self, action: #selector(yourController.yourFunction)) 
    yourObject.addGestureRecognizer(yourTapEvent) // adding the gesture to your object

func yourFunction(_ sender: AnyObject) {
    let yourTag = sender.view!.tag // this is the tag of your gesture's object
    // do whatever you want from here :) e.g. if you have an array of buttons instead of just 1:
    for button in buttonsArray {
      if(button.tag == yourTag) {
        // do something with your button
      }
    }
}

The reason for all of this is because you cannot pass further arguments for yourFunction when using it in conjunction with #selector.

If you have an even more complex UI structure and you want to get the parent's tag of the item attached to your tap gesture you can use let yourAdvancedTag = sender.view!.superview?.tag eg getting the UIView's tag of a pressed button inside that UIView; can be useful for thumbnail+button lists etc.

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