Twitter is a microblogging site that allows users to post brief, 140-character messages -- called "tweets" -- and follow other users' activities.

Why it's popular
Teens like using it to share quick tidbits about their lives with friends. It's also great for keeping up with what's going on in the world -- breaking news, celebrity gossip, etc.

What parents need to know:

• Public tweets are the norm for teens. Though you can choose to keep your tweets private, most teens report having public accounts (Pew Internet & American Life Project, 2013). Talk to your kids about what they post and how a post can spread far and fast.
• Updates appear immediately. Even though you can remove tweets, your followers can still read what you wrote until it's gone. This can get kids in trouble if they say something in the heat of the moment.
• It's a promotional tool for celebs. Twitter reels teens in with behind-the-scenes access to celebrities' lives, adding a whole new dimension to celebrity worship. You may want to point out how much marketing strategy goes into the tweets of those they admire.

Read more about Twitter on CommonSenseMedia.org.

Instagram is a platform that lets users snap, edit, and share photos and 15-second videos -- either publicly or with a network of followers.

Why it's popular
Instagram unites the most popular features of social media sites: sharing, seeing, and commenting on photos. Instagram also lets you apply fun filters and effects to your photos, making them look high-quality and artistic.

What parents need to know:

• Teens are on the lookout for "Likes." Similar to Facebook, teens may measure the "success" of their photos -- even their self-worth -- by the number of likes or comments they receive. Posting a photo or video can be problematic if teens post it to validate their popularity.
• Public photos are the default. Photos and videos shared on Instagram are public unless privacy settings are adjusted. Hashtags and location info can make photos even more visible to communities beyond a teen's followers if his or her account is public.
• Private messaging is now an option. Instagram Direct allows users to send "private messages" to up to 15 mutual friends. These pics don't show up on their public feeds. Although there's nothing wrong with group chat, kids may be more likely to share inappropriate stuff with their inner circles. Also, strangers can send private messages to users; kids then choose to open the message and view or discard the attached picture.
• Mature content can slip in. The terms of service specify that users should be at least 13 years old and shouldn't post partially nude or sexually suggestive photos -- but they don't address violence, swear words, or drugs.

Read more about Instagram on CommonSenseMedia.org.

Snapchat is a messaging app that lets users put a time limit on the pictures and videos they send before they disappear.

Why it's popular
Snapchat's creators intended the app's fleeting images to be a way for teens to share fun, light moments without the risk of having them go public. And that's what most teens use it for: sending goofy or embarrassing photos to one another. Snapchats also seem to send and load much "faster" than email or text.

What parents need to know:

• Many schools have yet to block it, which is one reason why teens like it so much (Pew Internet & American Life Project, 2013).
• It's a myth that Snapchats go away forever. Data is data: Whenever an image is sent, it never truly goes away. (For example, the person on the receiving end can take a screenshot of the image before it disappears.) Snapchats can even be recovered. After a major hack in December 2013 and a settlement with the FTC, Snapchat has clarified their privacy policy, but teens should stay wary.
• It can make sexting seem OK. The seemingly risk-free messaging might encourage users to share pictures containing inappropriate content.

Similar Apps

Confide

Burn Notice

Wickr

Read more about Snapchat on CommonSenseMedia.org.

Tumblr is like a cross between a blog and Twitter: It's a streaming scrapbook of text, photos, and/or videos and audio clips. Users create and follow short blogs, or "tumblelogs," that can be seen by anyone online (if made public).

Why it's popular
Many teens have tumblrs for personal use -- sharing photos, videos, musings, and things they find funny with their friends. Tumblelogs with funny memes and gifs often go viral online, as well (case in point: "Texts from Hillary").

What parents need to know:

• Porn is easy to find. This online hangout is hip and creative but sometimes raunchy. Pornographic images and videos, depictions of violence, self-harm, drug use, and offensive language are easily searchable.
• Privacy can be guarded, but only through an awkward workaround. The first profile a member creates is public and viewable by anyone on the Internet. Members who desire full privacy have to create a second profile, which they're able to password protect.
• Posts are often copied and shared. Reblogging on Tumblr is similar to re-tweeting: A post that's reblogged from one tumblelog then appears on another. Many teens like -- and in fact, want -- their posts reblogged. But do you really want your kids' words and photos on someone else's page?

Read more about Tumblr on CommonSenseMedia.org.

Google+ is Google's social network, which is now open to teens. It has attempted to improve on Facebook's friend concept -- using "circles" that give users more control about what they share with whom.

Why it's popular
Teens aren't wild about Google+ yet. But many feel that their parents are more accepting of it because they associate it with schoolwork. One popular aspect of Google+ is the addition of real-time video chats in Hangouts (virtual gatherings with approved friends), and some schools may use Google Docs for classroom assignments.

What parents need to know:

• Teens can limit who sees certain posts by using "circles." Friends, acquaintances, and the general public can all be placed in different circles. If you're friends with your kid on Google+, know that you may be in a different "circle" than their friends (and therefore seeing different information).
• Google+ takes teens' safety seriously. Google+ created age-appropriate privacy default settings for any users whose registration information shows them to be teens. It also automatically reminds them about who may be seeing their posts (if they're posting on public or extended circles).
• Data tracking and targeting are concerns. Google+ activity (what you post and search for and who you connect with) is shared across Google services including Gmail and YouTube. This information is used for targeting ads to the user. Users can't opt out of this type of sharing across Google services.

Read more about Google+ on CommonSenseMedia.org.

Vine is a social media app that lets users post and watch looping six-second video clips. This Twitter-owned service has developed a unique community of people who post videos that are often creative and funny -- and sometimes thought-provoking.

Why it's popular
Videos run the gamut from stop-motion clips of puzzles doing and undoing themselves to six-second skits showing how a teen wakes up on a school day vs. a day during summer. Teens usually use Vine to create and share silly videos of themselves and/or their friends and family.

What parents need to know:

• It's full of inappropriate videos. In three minutes of random searching, we came across a clip full of full-frontal male nudity, a woman in a fishnet shirt with her breasts exposed, and people blowing marijuana smoke into each other's mouths. There's a lot of funny, clever expression on Vine, but much of it isn't appropriate for kids.
• There are significant privacy concerns. The videos you post, the accounts you follow, and the comments you make on videos are all public by default. But you can adjust your settings to protect your posts; only followers will see them, and you have to approve new followers.
• Parents can be star performers (without knowing). If your teens film you being goofy or silly, you may want to talk about whether they plan to share it.

Read more about Vine on CommonSenseMedia.org.

Wanelo (Want, Need, Love) combines shopping, fashion blogging, and social networking all in one. It's very popular among teens, allowing them to discover, share, and buy products they like.

Why it's popular
Teens keep up with the latest styles by browsing Wanelo's "trending" feed, which aggregates the items that are most popular across the site. They can also cultivate their own style through the "My Feed" function, which displays content from the users, brands, and stores they follow.

What parents need to know:

• If you like it, you can buy it. Users can purchase almost anything they see on Wanelo by clicking through to products' original sites. As one user tweeted, "#Wanelo you can have all of my money! #obsessed."
• Brand names are prominent. Upon registering, users are required to follow at least three "stores" (for example, Forever21 or Marc Jacobs) and at least three "people" (many are other everyday people in Wanelo's network, but there are also publications like Seventeen magazine).
• There's plenty of mature clothing. You may not love what kids find and put on their wish lists. Wanelo could lead to even more arguments over what your teen can and can't wear.

Read more about Wanelo on CommonSenseMedia.org.

Kik Messenger is an app-based alternative to standard texting that kids use for social networking. It's free to use but has lots of ads.

Why it's popular
It's fast and has no message limits, character limits, or fees if you just use the basic features, making it decidedly more fun in many ways than SMS texting.

What parents need to know:

• It's too easy to "copy all." Kik's ability to link to other Kik-enabled apps within itself is a way to drive "app adoption" (purchases) from its users for developers. The app also encourages new registrants to invite everyone in their phone's address book to join Kik, since users can only message those who also have the app.
• There's some stranger danger. An app named OinkText, linked to Kik, allows communication with strangers who share their Kik usernames to find people to chat with. There's also a Kik community blog where users can submit photos of themselves and screenshots of messages (sometimes displaying users' full names) to contests.
• It uses real names. Teens' usernames identify them on Kik, so they shouldn't use their full real name as their username.

Read more about Kik Messenger on CommonSenseMedia.org.

Oovoo is a free video, voice, and messaging app. Users can have group chats with up to 12 people for free. (The premium version removes ads from the service.)

Why it's popular
Teens mostly use Oovoo to hang out with friends. Many log on after school and keep it up while doing homework. Oovoo can be great for group studying and it makes it easy for kids to receive "face to face" homework help from classmates.

What parents need to know:

• You can only chat with approved friends. Users can only communicate with those on their approved "contact list," which can help ease parents' safety concerns.
• It can be distracting. Because the service makes video chatting so affordable and accessible, it can also be addicting. A conversation with your kids about multitasking may be in order.
• Kids still prefer in-person communication. Though apps like Oovoo make it easier than ever to video chat with friends, research shows that kids still value face-to-face conversations over online ones -- especially when it comes to sensitive topics. Still, they sometimes find it hard to log off when all of their friends are on.

Similar Apps

Rounds

Read more about Oovoo on CommonSenseMedia.org.

Yik Yak is a free, location-aware, social-networking app that lets users post "anything and everything" anonymously through brief, Twitter-like comments, which are distributed to the geographically nearest 500 people who are also signed in to the app.

Why it's popular
Kids can find out opinions, secrets, rumors, and more. Plus, they'll get the bonus thrill of knowing all these have come from a 1.5-mile radius (maybe even from the kids at the desks in front of them!).

What parents need to know:

• It reveals your location. By default, exactly where you are is shown unless you toggle location sharing off. Each time you open the app, GPS updates your location.
• It's a mixed bag of trouble. This app has it all: cyberbullying, explicit sexual content, unintended location sharing, and exposure to explicit information about drugs and alcohol.
• Some schools have banned access. Some teens have used the app to threaten others, causing school lockdowns and more. Its gossipy and sometimes cruel nature can be toxic to a high school environment, so administrators are cracking down.

Read more about Yik Yak on CommonSenseMedia.org.

Ask.fm is a social site that lets kids ask questions and answer those posted by other users -- sometimes anonymously.

Why it's popular
Although there are some friendly interactions on Ask.fm -- Q&As about favorite foods or crushes, for example -- there are lots of mean comments and some creepy sexual posts. This iffy content is part of the site's appeal for teens.

What parents need to know:

• Bullying is a major concern. The British news website MailOnline reported that the site has been linked to the suicides of several teens. Talk to your teens about cyberbullying and how anonymity can encourage mean behavior.
• Anonymous answers are optional. Users can decide whether to allow anonymous posts and can remove their answers from streaming to decrease their profile's visibility. If your teens do use the site, they'd be best turning off anonymous answers and keeping themselves out of the live stream.
• Q&As can appear on Facebook. Syncing with Facebook means that a much wider audience can see those Q&As.

Read more about Ask.fm on CommonSenseMedia.org.

WhatsApp lets users send text messages, audio messages, videos, and photos to one or many people with no message limits or fees.

Why it's popular
The price is right; for teens who have a hard time keeping within the limits of a standard texting plan, the ability to send unlimited messages for free is a definite bonus.

What parents need to know:

• It's for users 16 and over. Lots of younger teens seem to be using the app, but this age minimum has been set by WhatsApp.
• It can be pushy. After you sign up, it automatically connects you to all the people in your address book who also are using WhatsApp. Beyond that, the app often encourages you to add friends who haven't yet signed up.
• Kids may need some limits. Although unlimited texting may save you cash, capping kids' communication can help them stay focused on the more important transmissions.

Read more about WhatsApp on CommonSenseMedia.org.

Omegle is a chat site (and app) that puts two strangers together in their choice of a text chat or video chat room.

Why it's popular
Being anonymous can be very attractive to teens, and Omegle provides a no-fuss opportunity to make connections. Its "interest boxes" also let users filter potential chat partners by shared interests.

What parents need to know:

• Users get paired up with strangers. That's the whole premise of the app. And there's no registration required.
• This is NOT an app for kids and teens. Omegle is filled with people searching for sexual chat. Some prefer to do so live. Others offer links to porn sites.
• Language is a big issue. Since the chats are anonymous, they're often much more explicit than those with a user who can be identified might be.

Similar Apps

Chatroulette

Read more about Omegle on CommonSenseMedia.org.

Yo. is a bare-bones social app that sends a short text message to friends and family, simply reading "Yo" (and speaking the word aloud). That's it.

Why it's popular
This admittedly silly concept has taken off big-time since the app's release in mid-2014. Although it may not seem like much, this single word has the potential to let friends and family know you're thinking of them and just wanted to say, you know, "Yo."

What parents need to know:

• It's relatively harmless -- but watch out for hackers. The app's simple design and explosive popularity has made it a target for hackers.
• Yo. may be a flash in the pan. Although your kid may be obsessed with sending "yo" greetings to everyone in her address book today, tomorrow could be a different story, as apps like this tend to have a shorter lifespan.
• Kids may need some limits. Although unlimited texting may save you cash, capping kids' communication can help them stay focused on the more important transmissions.

Read more about Yo. on CommonSenseMedia.org.

Whisper is a social "confessional" app that allows users to post whatever's on their minds, paired with an image.

Why it's popular
With all the emotions running through teens, anonymous outlets give them freedom to share their feelings without fear of judgment.

What parents need to know:

• Whispers are often sexual in nature. Some users use the app to try to hook up with someone nearby, while others post "confessions” of desire. Lots of eye-catching nearly nude pics accompany these shared secrets.
• Content can be dark. People normally don't confess sunshine and rainbows; common Whisper topics include insecurity, depression, substance abuse, and various lies told to employers and teachers.
• Although it's anonymous to start, it may not stay that way. The app encourages users to exchange personal information in the "Meet Up" section.

Similar Apps

Secret

Pheed

Streetchat

Read more about Whisper on CommonSenseMedia.org.

Parents need to know that Tinder is a photo and messaging dating app for browsing photos of potential matches within a certain mile radius of the user's location. Swipe right to "like" a photo or left to "pass." If a person whose photo you "liked" swipes "like" on your photo, the app allows you to message each other. Along with seeking and messaging matches, users can post "moments," which are images and messages that exist for 24 hours and then disappear. Tinder's terms of use indicate that it can be used by anyone 13 and up, but the app's widespread reputation as a hookup site, its use of location, and its lack of privacy settings make this a no-go for teens.

Similar Apps

MeetMe

Tagged

Badoo

Read more about Tinder on CommonSenseMedia.org.

Vault allows the user to hide photos, videos, text messages, contacts and apps. They are only accessible by password. Alarmingly, the user can create a decoy vault that can be loaded with content to prevent an interested party from seeing the truly hidden content. uKnowKids.com discusses hiding and obfuscation apps further.

Similar Apps

KeepSafe

Poof!

Read more about Tinder on uKnowKids.com.