Music app developer Smule today launched Smule Pass, a new cross-app subscription to connect all of its apps under a single premium plan.

Previously, Smule users had to purchase individual subscriptions for its apps. With Smule Pass, you’ll now be able to pay once and have access to song libraries, unlimited storage, audio effects and instruments across its four main apps – Magic Piano, Sing! Karaoke, Guitar! and AutoRap. The unified plan should make it easier for Smule to drive cross-app interactions, such as recording a piano track for a song that another user sings in the karaoke app.

Smule’s 250,000 existing subscribers will receive a free upgrade to Smule Pass. New users will pay $7.99 per month or $39.99 per year for the service.

Smule oversees a musical empire of 18 million monthly users. It topped $20 million in sales last year and is on track to hit $35 million this year.

Switching to a single subscription is a risky move for Smule, as it will earn less revenue from its existing users that currently pay for multiple subscriptions. Smule CEO Jeff Smith said the company expects to see revenue dip in the short-term, but that it will end up with a much more engaged user base in the long-run.

Smule’s business model has evolved over several generations of apps. It started out in 2008 with paid apps for a complete install before moving to in-app purchases. It added on a virtual currency to account for micro-transactions, and then switched to single-app subscriptions. With its latest multi-app model, Smule is making a play for a full-on musical mobile platform, which will hopefully have a lower subscriber churn rate than individual app plans.

“For us [Smule Pass] makes sense, because it is a platform. It’s no longer a set of discrete applications. It’s a common fabric of users that are creating more and more content across the applications,” Smith said.