After 2 days on this problem
CATextLayer *text = [CATextLayer layer];
text.string = @"Your Text";
text.frame = CGRectMake(0, 0, 320, 50);
CGFontRef font = CGFontCreateWithFontName((CFStringRef)@"HelveticaNeue-UltraLight");
text.font = font;
text.fontSize = 20;
text.foregroundColor = [UIColor whiteColor].CGColor;
[text display];
[aLayer addSublayer:text];
[aLayer display];
The secret is calling [CALayer display] method