In my app I am using custom font which working perfectly fine. But I need the button text to be bold. I googled it there is only for System fonts.
Code
button.titleLabel.font = [UIFont fontWithName:@"YanaR" size:20.0];
Thanks for your help guys.
That's because fonts don't magically make themselves bold. Bold fonts are designed separately. I'm afraid there is no answer to this question, apart from thickening the stroke of the lines, which would probably be in breach of your font agreement.