Apple boosts the performance of your iPhone with iOS 13. Compared to iOS 12 FaceID is 30% faster at unlocking your iPhone.
Apple also changes it up so that Apps can launch twice as fast when you tap on them. This makes the whole iPhone experience feel snappier.
Apps are also now smaller than before so you can download them faster, and so they use up less space.
You'll get 50% smaller downloads and 60% smaller updates when on iOS 13.