iOS 7 sizeWithAttributes: replacement for sizeWithFont:constrainedToSize

well you can try this :

NSDictionary *attributes = @{NSFontAttributeName: [UIFont fontWithName:@"HelveticaNeue" size:14]};
// NSString class method: boundingRectWithSize:options:attributes:context is
// available only on ios7.0 sdk.
CGRect rect = [textToMeasure boundingRectWithSize:CGSizeMake(width, CGFLOAT_MAX)
                                          options:NSStringDrawingUsesLineFragmentOrigin
                                       attributes:attributes
                                          context:nil];

This is how I did it:

    // Get a font to draw it in
UIFont *font = [UIFont boldSystemFontOfSize: 28];

CGRect textRect;
NSDictionary *attributes = @{NSFontAttributeName: font};

// How big is this string when drawn in this font?
textRect.size = [text sizeWithAttributes:attributes];

// Draw the string
[text drawInRect:textRect withAttributes:attributes];