In your AppDelegate class import this file:
#import "CKSelectedTableViewCellFactory.h"
and set the Selected background color and corner radius, defaults are [UIColor lightGrayColor] and 5.0
CKSelectedTableViewCellFactory.sharedInstance.backgroundColor = UIColor.redColor;
CKSelectedTableViewCellFactory.sharedInstance.cornerRadius = 5.0;
To use in a UITableView:
cell.selectedBackgroundView = [CKSelectedTableViewCellFactory.sharedInstance selectedBackgroundViewForTableViewCell:cell inTableView:tableView atIndexPath:indexPath];