Simple Example Grid: 1. Create ViewBasedApplication 2. Add -> NewFile -> Cocoa Touch Class -> Objective-C-Class(UIView) -> ExampleGrid 3. Open the already existing ExampleGridViewController.xib 4. Click on the View(In the list below Files'Owner and FirstResponder) -> Change the ClassIdentity to your Created ExampleGrid -Class 5. Add the following  example-function to the ExampleGrid-Class:

- (void)drawRect:(CGRect)rect {
  //image url
  UIImage *myImage = [UIImage imageWithData: [NSData dataWithContentsOfURL: [NSURL URLWithString: @"http://sammlungen-archive.zhdk.ch/media/thumbnails/19-0279.jpg"]]];
  for(int rowIndex = 0; rowIndex < 4; rowIndex++) {
    for(int colIndex = 0; colIndex < 6; colIndex++) {
      NSLog(@"currentColumn%",colIndex);
      UIImageView *myImageView = [[UIImageView alloc] initWithImage:myImage];
      CGRect frame = myImageView.frame;
      frame.origin.x = frame.size.width * colIndex;
      frame.origin.y = frame.size.height * rowIndex;
      myImageView.frame = frame;
      [self addSubview:myImageView];
      [myImageView release];
    }
  }
}

ref:  http://www.iphonedevsdk.com/forum/iphone-sdk-development/12858-generate-grid-images.html