Learning how to use different features on your iPhone can feel like a constant trial and error. Just when you feel like you've maybe mastered all there is to know, a new iOS update hits, and there are 10 more things to learn.But, while you might have heard about some of the biggest new components, such as Night Shift and password protection for your Notes in the latest iOS 9.3 updates, there are some iOS 9 features that may have slipped under the radar. Did you know that you can make your iPhone read emails to you, for example? Or that you can make calls over Wi-Fi, instead of trying to talk over an abysmal cellular connection?Here are six tricks to learn before another iOS update — and the new iPhone — arrive.