You can add emoji emoticons to the title or the body of your iOS, Android, Windows or web push notifications.

If you want to insert an emoji in your message you can:
Chrome 68+: Right-click any text field and select "Emoji" or "Emoji & Symbols".
Windows: Simply press the Windows key + the period button to display Windows's emoji keyboard on Windows 10. In case you are using an older version of Windows, you can copy-paste an emoji from emojipedia: iOS / Android / Windows.
Mac: Press CTRL + CMD + Space to display the emoji keyboard and pick an emoji.
Everywhere: Copy emojis from Emojipedia (https://emojipedia.org/) and paste it in your message
Firefox extension: Use the emoji cheatsheet https://addons.mozilla.org/en-US/firefox/addon/emoji-cheatsheet/
Chrome extension: You can use a third-party extension like Emoji Keyboard by EmojiOne https://chrome.google.com/webstore/detail/emoji-keyboard-by-emojion/ipdjnhgkpapgippgcgkfcbpdpcgifncb
🚧 Important note
On Android, emojis may look different on your users devices: