How to create a UITableViewCell with a transparent background

If both the other options didn't work try this

UIView *backView = [[[UIView alloc] initWithFrame:CGRectZero] autorelease];
backView.backgroundColor = [UIColor clearColor];
cell.backgroundView = backView;

This is actually answered in the docs of UITableViewCell. So while you do have to setup transparency on your controls, the actual cell background color must be set per below.

"Note: If you want to change the background color of a cell (by setting the background color of a cell via the backgroundColor property declared by UIView) you must do it in the tableView:willDisplayCell:forRowAtIndexPath: method of the delegate and not in tableView:cellForRowAtIndexPath: of the data source. Changes to the background colors of cells in a group-style table view has an effect in iOS 3.0 that is different than previous versions of the operating system. It now affects the area inside the rounded rectangle instead of the area outside of it."

https://developer.apple.com/documentation/uikit/uitableviewcell