[textView setFont:[UIFont boldSystemFontOfSize:15]];
or
[textView setFont:[UIFont systemFontOfSize:15]];
http://stackoverflow.com/questions/6517135/how-to-change-the-uitextview-font-size
[textView setFont:[UIFont boldSystemFontOfSize:15]];
or
[textView setFont:[UIFont systemFontOfSize:15]];
http://stackoverflow.com/questions/6517135/how-to-change-the-uitextview-font-size