Children are watching YouTube in their tens of millions, at least. From popular TV cartoons and characters to nursery rhymes to singalong Frozen songs to Minecraft gamers to toy-unboxers… And now there’s an official app for that: YouTube Kids.

It’s good timing, because the kids are definitely on YouTube, and there’s plenty of entertaining and/or educational stuff for them to watch there. The problem for parents is that there’s also a lot of videos that aren’t so child-friendly, and it can be a bit easy to slip from the former into the latter.

For example, one minute your child might be watching a video with their favourite TV character, and the next, they might be watching an adult’s parody of that show with swearing or other unsuitable content. Or a young child might be watching cute animal videos, and then stray into videos of not-so-cute animals tearing chunks off one another.

So, this is why YouTube Kids should be a good thing: it’ll only feature videos and channels that YouTube has pre-selected as safe for children. The app is available today for iOS and Android devices, although here’s the bad news: for now, it will only be available in the US. We’re hopeful of launches elsewhere in the world soon, though.

The app is based around four categories: Shows, Music, Learning and Explore. The first three are self-explanatory, and the fourth covers just about anything else children would watch on YouTube.

There’s also a search feature – used by typing or speaking – to look for specific subjects or shows. Don’t worry: if your child searches for something inappropriate (“sex” being the obvious example) they’ll get a friendly but firm message suggesting they search for something else instead. You can also set a timer to govern how long your children use the app.

YouTube Kids is free to download and use, and it won’t ask children to create a YouTube account or log in to a parent’s account. That’s reassuring on privacy grounds, although for now it also means the app won’t learn your child’s tastes and make recommendations based on their favourite videos. There will be ads around the videos, but YouTube says it’s carefully screening them for suitability.

Also missing: an offline mode, so for now this isn’t the answer to long car, train or plane trips, or holiday cottages with no internet access. “This is the first step toward reimagining YouTube for families, but with your help, the app will continue to get better over time,” explains product manager Shimrit Ben-Yair on YouTube’s blog – so that feature could be coming in the future, if enough people request it.

YouTube Kids is a free download for Android from the Google Play store, and a free download for iPhone and iPad from Apple’s App Store.