Social-media apps Instagram and Vine just got a lot more social, thanks to new features that let you tag or mention friends in photos (Instagram) and videos (Vine). Vine also got a new feature that lets you capture video of yourself eating Oreos. Seriously. More on that in a minute.\n\tInstagram, the free photo-sharing app for iOS and Android, now has an "Add People" option that lets you tag people in your photos. Instead of calling out friends in photo captions, you can now tag them in photos using their Instagram ID by tapping their image. If you don\u2019t know a user's ID, typing the name usually (but not always) helps locate them.\n\tWhen others tag you in photos the images appear in a new "Photos of You" section on your profile page. And an "Add Manually" option in the "Photos of You" section lets you prevent someone from, say, tagging a mortifying photo of you dressed up as a Chihuahua at the office Cinco de Mayo party. (You might not have been mortified, but your office mates? That\u2019s another story.)\n\tInstagram on Android (left); Vine on iOS (right)\n\tTwitter\u2019s free Vine six-second video-recording\/sharing app, which is still only available for\u00a0iOS, now lets you mention other Vine\/Twitter users by their usernames. When you type \u201c@\u201d and the user\u2019s account name in a caption, Vine searches to find the account, and then automatically links it to your caption.\n\tPeople mentioned in captions receive notifications when posts go live. Unfortunately, just as you can\u2019t pre-approve mentions of your Twitter account name in someone else\u2019s Twitter mention or "tweet," you also can\u2019t pre approve Vine video in which you\u2019re mentioned.\n\tVine also got a new feature that's seemingly designed for narcissists with a lot of free time on their hands.\u00a0You can now use the iPhone\u2019s front-facing camera for video recording. Check out the #Selfie videos in Vine to see fascinating videos of people eating tacos, people eating Oreos, people eating, well, anything and everything.