YouTube Music also comes with a free YouTube Red trial / Andrew H. Walker/Getty Images for YouTube

YouTube is trying to capitalise on its position as the world's most popular music streaming service with a standalone app

YouTube has just launched YouTube Music - a standalone app dedicated to music streaming and recommendation.

Obviously, YouTube is primarily a video site - but it's also the world's most-used music streaming service, far surpassing purpose-built apps like Spotify and Apple Music in popularity.

The launch of YouTube Music will make this title a little more 'official', as well as giving the millions of people who listen to music on YouTube every day a better experience.

It seems a little odd that YouTube Music will be competing with Google Play Music, created by YouTube's parent company. But it's a smart move considering YouTube's ubiquity.

YouTube Music has all the same tracks as its competitors, and users can listen to whole albums and single songs like anywhere else.

However, YouTube is really pushing the new app's recommendation service - any song, music video or artist starts a non-stop playlist that will play similar tracks. Users can also choose to switch the music video off, in case they want to save their battery or data.

And a Home tab at the top of the app will take note of what you listen to and constantly update with recommended tracks.

There's also 'Trending' and 'On the Rise' tabs that track what everyone else is listening to, and a Top 40 chart.

Most importantly for YouTube, it's going to be an important place to sell subscriptions to YouTube Red - YouTube's new paid-for service that eliminates ads and gives a bigger cut of revenue to video creators.

YouTube Red costs $10 a month in the US, but users will get an automatic 2-week free trial as soon as they sign in to YouTube Music.

YouTube will be hoping that by giving users a taste of ad-free videos, an offline mode and (finally) background listening, they'll want to start paying when the trial is up.

Google Play, Spotify and Apple Music are all jostling for first place, despite offering a fairly similar service. YouTube Music stands out from the pack because it offers such a huge range of music videos, as well as instant playlists and the recommendation feature that it's putting front and centre.

It'll also appear like a smaller commitment to many users, too - signing up to Spotify or Apple Music seems like a big deal, but most people already use YouTube for music anyway, so paying for their service might seem more natural.

The free app launched for iOS and Android in the US on Thursday, but there's no word on when it could come to the UK.

YouTube Red hasn't hit the UK yet either, but a YouTube spokeswoman told The Independent last month that it's likely to arrive soon - so we'll probably see YouTube music land at a similar time.