You can change the size and font of your UILabel with animation like bellow .. here I just put the example of how to change the font of UILabel with transform Animation ..

    yourLabel.font = [UIFont boldSystemFontOfSize:35]; // set font size which you want instead of 35    yourLabel.transform = CGAffineTransformScale(yourLabel.transform, 0.35, 0.35);     [UIView animateWithDuration:1.0 animations:^{        yourLabel.transform = CGAffineTransformScale(yourLabel.transform, 5, 5);    }];

I hope this helpful to you..

For 2017 onwards....

Swift 3.0, 4.0

UIView.animate(withDuration: 0.5) {     label.transform = CGAffineTransform(scaleX: 1.1, y: 1.1) //Scale label area }

Critical:

The critical point to avoid blurring is you must begin with the biggest size, and shrink it. Then expand to "1" when needed.

For quick "pops" (like a highlight animation) it's OK to expand beyond 1 but if you are transitioning between two sizes, make the larger size the "correct" normal one.

I've created UILabel extension in Swift.

import UIKitextension UILabel {    func animate(font: UIFont, duration: TimeInterval) {        // let oldFrame = frame        let labelScale = self.font.pointSize / font.pointSize        self.font = font        let oldTransform = transform        transform = transform.scaledBy(x: labelScale, y: labelScale)        // let newOrigin = frame.origin        // frame.origin = oldFrame.origin // only for left aligned text        // frame.origin = CGPoint(x: oldFrame.origin.x + oldFrame.width - frame.width, y: oldFrame.origin.y) // only for right aligned text        setNeedsUpdateConstraints()        UIView.animate(withDuration: duration) {            //L self.frame.origin = newOrigin            self.transform = oldTransform            self.layoutIfNeeded()        }    }}

Uncomment lines if the label text is left or right aligned.