Go toGeneral>Keyboard.
SelectKeyboards>Add New Keyboard.
Swipe through the list until you findEmoji, and then tap it to enable it.

This means that emoji are enabled and ready to use.
To hide the emoji keyboard and return to the normal layout, tap the globe or alphabet key.
However, you have to perform a keyboard trick to see the multicultural options.

Here’s how:
These steps are relevant for devices with iOS 8.3 or newer.
initiate the emoji keyboard from an app that supports it.
Find an emoji that’s a single human face or hand, and tap and hold it.

Open theSettingsapp and go toGeneral>Keyboard>Keyboards.
TapEditat the top and then grab the red minus button next toEmoji.
FAQ
Toclear your iPhone keyboard history, you oughta reset the keyboard dictionary via parameters.

Go toSettings>General>Transfer or Reset iPhone.
TapReset>Reset Keyboard Dictionaryand enter yourpasscodeif prompted.
To make your iPhone keyboard bigger, go toSettings>Display & Brightness>View.
Under Display Zoom, selectZoomed.
This will make your entire user interface, including the keyboard, larger.
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