Those with Nokia’s Windows Phone-based Lumia handsets are probably familiar with Nokia Music, an app that provides access to a free Internet service called Mix Radio. Nokia this weekend announced Music+, a coming paid service that improves on the free version and undercuts pricing on Xbox Music Pass.

There is one major caveat, however: While Music+ will allow PC-based playback via a web app, it remains an exclusive to the firm’s Lumia handsets. Those with HTC or Samsung Windows Phone devices will not be able to use Music+.

Nokia Music+ will be available soon, Nokia says, and will cost just $3.99 a month. By comparison, Xbox Music Pass costs $9.99 per month (or about $8.25 per month if you sign up for a year of service). And it appears to be very similar to Microsoft’s offering.

Nokia Mix Radio will continue as a free service, Nokia says. But those who sign up for Music+ will receive the following improvements:

Unlimited song skipping. Whereas Nokia Music with Mix Radio prevents you from skipping too many songs at once, similar to free versions of other Internet radio services, Music+ lets you skip from track to track, similarly to Xbox Music Pass.

Unlimited downloads. With the free service, you can download up to four Mixes (each of which contains hours of music) and play them offline, without an Internet connection. The paid service removes these limit, so you can download as much music for offline playback as you wish.

Higher quality. Nokia Music+ provides music downloads with “eight times” the quality of the free service. Nokia notes that you can configure the app to download high quality only when you’re on Wi-Fi to save data fees.

Lyrics. Music+ will provide lyrics to the currently playing song via a scrolling list, a Karaoke-style format, or a display you can scroll up and down.

Windows PC support (sort of). ANokia Music+ subscription also lets you access the service without your phone: You can use the service via a web app on your PC, smart TV or other connected devices.

Nokia says that Music+ will roll out in the next few weeks. I’m of course curious, but until or unless this app is available on other Windows Phone handsets, it’s only partially interesting.