On stock Android phones, this is Hangouts by default.


Samsung phones come with their own messaging app called “Messages”.;
,, The keyboard will appear.
 This is in the lower right corner of the keyboard.
 The selected emoji will be added to your message.


Swipe left or right or tap the category icons at the top of the keyboard to browse through various emoji.
Tap the ":-)" button to switch to ASCII formatted emoticons. These can be useful for communicating with non-smartphone users, since they may not be able to render emoji sent from your device.
Tap ABC to return to the normal keyboard
Open your messaging app.
Tap a conversation.

,
Tap the text field.
Tap the smiley icon.
Tap an emoji.
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