Marvel Entertainment today released Marvel Unlimited on the Apple App Store for iPhone and iPad, a digital comics subscription program.

Marvel Unlimited already exists as a browser-based service, but now its coming to mobile devices, with access to 13,000 back issues as of today and syncs all downloaded comics across all devices. If a user is already paying for a subscription for the web-based version, they can use the same subscription for the mobile app. Marvel Unlimited’s subscription is priced at $10 a month or $60 a year, for a limited time.

Marvel Unlimited isn’t without limitations. At launch, users can only make available six issues for offline reading, according to Gizmodo. Also, the comics available for reading in Marvel Unlimited are at least six months old, from its original printing. Some major titles such as the entire Iron Man collection aren’t available for the service either. Technology-wise, the app is built in HTML5, and not in an native format such as Objective-C for iOS or Java for Android.

Marvel Unlimited will be competing with other comic reading apps available for both iOS and Android such as Comics by Comixology, DC Comics by DC Entertainment and Marvel’s own Marvel Comics.

Marvel Unlimited will be coming to Android soon.