Simple method for creating expanding UITableView rows that expand in an animated fashion when accessory button is tapped. What you do with the extra space in the expanded row is up to you.

gistfile1.txt

- (void) tableView:(UITableView *)tableView accessoryButtonTappedForRowWithIndexPath:(NSIndexPath *)indexPath {
    NSLog(@"Detail Disclosure Tapped");
        // Set expanded cell then tell tableView to redraw with animation
    self.expandedRow = indexPath;
    [self.tableView beginUpdates];
    [self.tableView endUpdates];
}

- (CGFloat) tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath {
    
    if ([indexPath isEqual:self.expandedRow]) {
        return EXPANDED_HEIGHT;
    }
    
    return NORMAL_HEIGHT;
}