VoiceOver feature in iPhone reads out the word as we use the iPhone. You can think VoiceOver feature is for blind users of iPhone who wants to use the feature and iPhone reads out for them. Here are the steps on How to turn on VoiceOver in iPhone.
Step 1: Go to “settings” of your iPhone
Step 2: Tap on the “General” settings
Step 3: Tap on “Accessibility” option under General settings
Step 4: Tap on “VoiceOver” settings to turn on this feature on your iPhone
As shown in the picture above, you can also turn on other features like speak hints, Pitch change, sound effects etc. Once the VoiceOver is turned on, everything that you touch is read out by iOS.