It seems like every time you turn around, there's a new app -- or type of app -- that's popular with tweens and teens. While the old standbys like Snapchat and Instagram are still going strong, there's no shortage of social media apps that are popular but not necessarily household names. And social media apps are just the beginning. Of course, it's nearly impossible to keep up with every hot new app, which makes knowing the risky features -- like interaction with strangers, anonymity, privacy concerns, and iffy content -- a solid first step. But it's still important to know the specifics of what's on your kid's device and whether or not you'll allow it to stay there.

Check out the titles below so you have a sense of what your kid -- or your kid's friends -- may be using and what you need to know about each app. And since all of these are free, be aware that the developers make money on them through in-app purchases, ads, selling user data, or all of the above!

Kind of like Twitch and YouTube, BIGO LIVE lets teens stream live video of themselves that other users can see and comment on in real time. You can also receive and send "Beans" -- BIGO's term for virtual gifts -- that cost real money. You can level up and improve your ranking by logging in every day and sending gifts. The platform is designed for people who supposedly want to get famous, but it seems to be filled mainly with people competing for gifts.

What parents need to know

BIGO has a lot of mature content, including sexy talk and clothing, and users' comments are often predatory and explicit. Also, its focus on status and spending money, as opposed to creativity and talent, makes it feel shallow.

Similar apps: Tagged - Chill, Chat & Go Live! and imo video calls and chat.

In this simulation game, you're assigned an identity to play through the entire game, from infancy to death. As you play -- and your character gets older -- you can make text-based choices about how to make money, spend time, and develop relationships with pretend profiles (which aren't connected to real people). Those choices determine your levels of happiness, health, smarts, and appearance. When you die, you can start all over.

What parents need to know

While kids can't engage in actual risky behavior, BitLife exposes them to mature ideas. As your character gets older, you can choose to "hook up" with the pretend profiles, drink, do drugs, gamble, and commit crimes. (On the other hand, you can make healthy choices such as going to the gym and meditating.) It's also easy for players to become overly fixated on the idealized world of sim games. Because you can start over when your character dies, there's the promise of endless free play, which could be a concern if your teen is really into the game.

Similar app: Reigns

This app is all about connecting with strangers. Once you sign up using a phone number or your Facebook account, you can get matched instantly with a stranger -- and both you and they appear on camera. Or you can swipe Tinder-style until you like someone and they like you (by tapping a heart). You can also enable location tracking to be paired with someone nearby.

What parents need to know

Video-chatting with strangers can be risky for teens. When it's paired with location, it's a no-go. Also, while HOLLA supposedly bans iffy content -- like nudity and violence -- user reviews indicate that masturbation, fake identities, and negative comments are common. The app's age-matching is a red flag, too. It was easy for our tester to pose as a 13-year-old and get paired with 16- and 17-year-olds.

Similar apps: Yubo, MeetMe - Chat and Meet New People, Spotafriend - Teen Meeting App To Make New Friends, ChatLive, Random Video Chat

Using the website or the app, users interact through elaborate 3D avatars. You can dress them up, place them in public or private rooms, and follow other users and chat with them. You can also buy a wide variety of objects using virtual coins -- earned primarily through taking surveys or watching ads or through buying outright with real money. There's no game or goal other than acquiring outfits, rooms, furniture, and other items or chatting with other users.

What parents need to know

Virtual sex and user privacy are the main issues for teens in IMVU. The avatars sport highly stereotypical body types with big muscles or breasts, and many of the outfits are skimpy. It also appears that users generate a following on other platforms by sharing their IMVU usernames, which invites more contact with people they don't know. Finally, the search term "IMVU sex" results in lots of advice about how to have (virtual avatar) sex and where to find it in IMVU.

Similar app: Avakin Life

Similar to the video lip-synching service Tik Tok, Like lets you create short videos that often involve lip-synching. You can also follow other users, climb a leaderboard (based on how many likes you've gotten), send direct messages, and send virtual gems -- that cost real money -- to other users.

What parents need to know

Also like Tik Tok, Like features mature music and dancing and allows strangers to interact. The leaderboard motif encourages kids to post frequently and gather likes -- basically to keep kids on the app longer and increase their circle of friends (which only benefits the company). So while it can be creative and fun, it's best used with strict privacy settings by teens who are savvy about keeping themselves safe online.

Similar apps: Funimate, Triller, and Lomotif. VSCO is another popular photography-related app, but it's not about performance or music and tends to be tamer.

Yolo got popular fast because it only works with Snapchat, which makes it an easy add-on. It lets users ask anonymous questions and get "feedback." Teens can then choose whether or not to make the responses public.

What parents need to know

Tweens and teens love anonymous feedback apps because they're concerned about what others think about them and want the freedom to be "honest" online. Because teens love them, these apps keep turning up like a bad penny. Like Sarahah as well as Lipsi, which is often used in conjunction with Instagram, lots of posts are positive, but anonymous feedback services are generally a recipe for bullying, trolling, and hurt feelings.

Similar apps: Lipsi, Sarahah, Tellonym, Profoundly: Anonymous Chats, LMK: Anonymous Polls

This app lets you take a picture of a homework problem or question and get an answer and explanation in return, similar to Photomath - Camera Calculator. Because it's more focused and filtered than an open internet search, the results are more targeted and helpful (in other words, it gives you the answers).

What parents need to know

The biggest concern is cheating: If your kid decides to use this app as an easy way out of homework, they'll lose a lot of learning. Secondly, since the answers come from the internet, they aren't always right. Used with good judgment (and monitoring by a parent), a teen could legitimately use Socratic to dig into tough concepts, but it's pretty easy to use for cheating.

Similar apps: Photomath - Camera Calculator, Mathway, Got It Study - Homework Help

This app features dynamic stories that let users make choices about the direction the story takes. Most center on subjects teens care about, primarily romantic relationships. Users can also create their own stories and participate in user discussion forums.

What parents need to know

On the surface, this app has a lot to offer: It gets kids reading and allows them to create stories. Unfortunately, most of the stories have sexual content or innuendo, a focus on appearance, substance use, and swearing. There's also quite a consumer push that encourages kids to spend real money to get the rest of a story faster. So while this app has a lot of positive potential and can provide a creative outlet for kids, it also has a lot of iffy messages that aren't appropriate for younger teens.

Similar apps: Hollywood Story, My Story: Choose Your Own Path, Superstar Life