batchupdates.m

    int resultsSize = [self.dataController.products count]; //data is the previous array of data
    [self.dataController.products addObjectsFromArray:products];

    [self.productsView performBatchUpdates:^{
        NSMutableArray *arrayWithIndexPaths = [NSMutableArray array];
        for (int i = resultsSize; i < resultsSize + products.count; i++) {
            [arrayWithIndexPaths addObject:[NSIndexPath indexPathForRow:i inSection:0]];
        }
        [self.productsView insertItemsAtIndexPaths:arrayWithIndexPaths];
    }
                                completion:nil];