The launch of the app (via TechCrunch) comes on the day Sony officially rolls out subscription packages for the cloud-based service.
Previously gamers were only able to rent titles on an individual basis but now they can sign up for a monthly or quarterly all-you-can-eat access to over 100 games.
Gamers in North America can pay $20 a month (around £13) or $45 a quarter (about £30) for access to games like inFamous, The Last of Us and Batman: Arkham City.
PlayStation Now is available on devices other than the PS4 (including Samsung’s new Tizen-based Smart TVs), but owners of the next-gen console are getting first dibs on the subscription packages.
The subscriptions mean gamers can play titles for as long as they want without restrictions, while all game saves are registered in the cloud.
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Gamers in the U.S. and Canada can jump aboard now by downloading the PlayStation Now app from the PS Store, but sadly Brits will have to wait their turn. PlayStation Now isn’t expected to hit Blighty until later this year, when a beta version is scheduled to go live.
When it eventually arrives, those without a PlayStation console (PS3, PS4 and PS Vita) will still be able to jump on board thanks to a host of apps on Sony and non-Sony devices.
Users will, of course, be able to play the games by hooking up a DualShock 4 controller wirelessly to their secondary device.