You have not set the frame of your text as for the if statement, why it exists is beyond me.
add the Following code:
helloWorldLabel.frame = CGRectMake([X position of top-left corner here], [Y position of top-left corner here], [how wide you want the object to be], [how tall you want the object to be];
For example you you wanted a 300 x 300 box starting at the top left of the screen you would do
helloWorldLabel.frame = CGRectMake( 0, 0, 300, 300);
Hopefully this helps