или вы строите это сами так:
-(void)createGrid
{
int col = 0;
int row = 0;
for (int i = 0; i<12; i++)
{
col = i % 2;
row = i / 2;
self.gridItem = [[ItemViewController alloc] init];
[self.gridItem.view setTag:i];
[self.scrollView addSubview:self.gridItem.view];
[self.gridItem.view setFrame:CGRectMake(col*160, row*160, 160, 160)];
[self addChildViewController:(UIViewController*) self.gridItem];
}
}