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Open Facebook. Find a post to comment on. Tap Comment. Open your phone's emoji keyboard. Select an emoticon. Use the built-in emoticon feature. Tap Post.
Tap the Facebook app icon, which resembles a white "f" on a dark-blue background, to open the News Feed if you're already logged in. If you aren't already logged into Facebook, enter your email address (or phone number) and password first. Scroll down the News Feed until you find a post that you want to comment on. You can also create a status by tapping the status box near the top of the News Feed. It's the speech bubble icon below the post. Skip this step if you're creating a status. To do so:   iPhone - Tap the smiley-face icon in the bottom-left corner of the keyboard. If you have more than two keyboards, you'll tap the globe-shaped icon and select the Emoji option instead.  Android - Tap the smiley-face icon next to the spacebar, or tap and hold the keyboard and then select the emoji keyboard. On some Android phones, you can tap and hold the microphone icon and then select the emoji keyboard in the pop-up menu. In the emoji keyboard, tap the emoticon(s) that you want to post on Facebook. Doing so will type them automatically. You can tap one of the tabs at the bottom of the keyboard to view different groups of emoticons. If you can't find an emoji keyboard on your phone or tablet, you can tap the smiley face icon in the far-right side of the comment field (or the yellow smiley face in the status box) and then select an emoticon in the resulting menu. It's to the right of your comment. If you created a status, you'll find Post in the upper-right side of the screen instead. Doing so publishes your comment or status, emoticons included.