There's one thing every comic fan has been yelling about for years: Why isn't there a subscription service that lets you pay for an all-you-can-eat monthly dose of comics? Marvel just did it. Marvel Unlimited, formerly MDCU, is on iPads and iPhones now.

Marvel Unlimited is a new app, separate from the Marvel app already in the store. The app is an extension of the new HTML5 reader that Marvel Digital Comics Unlimited rolled out recently, but much more convenient. It's only on iOS for now, but will be on Android "soon". You can also just use Android's browser, but that's not a very fun experience. The subscription is the same as the web-based version, so if you already subscribe to MDCU, you can use the app, too. If not, subscriptions are $10 per month, or a "limited time" annual subscription for $60 ($5 per month).

Some specifics: It's got access to 13,000 back issues, lets you add comics to your library like you would in Spotify or Rdio, can store six issues for offline reading (ugh, yes, we'll get to that), sorts by character, series, creator, or events (think Civil War, Onslaught, etc.), and syncs your downloaded comics across all your devices.

Marvel Unlimited: Marvel's Spotify for Comics Is Out Now for iOS

Having played with it a bit, the HTML5 reader isn't the fastest or most responsive, especially on pinch-to-zoom (which you can see in the video), but it's mostly acceptable. Still, it's a long way from the smoothness of native apps like the Comixology Marvel app, Kindle or iBooks. Marvel said it's a "trade off for having the same reader and experience in the app as you have on the web." It displays in very high res (via progressive download), even when you haven't downloaded the full book for offline reading. Marvel couldn't confirm if the resolution is the same as the retina-level Comixology books, but they looked tack-sharp as a full page.

The comics available through MU are all at least six months old, and while Marvel wouldn't commit to every title making it into the service, SVP of Marvel Digital Peter Phillips told us most major titles "should be in there at six months; we're pretty timely with that." Basically, it's like waiting for the trade.

Marvel Unlimited: Marvel's Spotify for Comics Is Out Now for iOS

But Philips added, "It's more of a borrow function, meant to be used in tandem with the Marvel app." Which explains the painfully low six issues available for offline reading. That's meant to be a full storyline, but won't get you through an average length plane ride. And it's positively anemic compared to the save for later features of Spotify, Rdio, or even Xbox Music, which like Marvel also sells the stuff available on its subscription. If you make enough noise about it, there's a decent chance Marvel can be moved off of that number. Something like 12 or 15 would be infinitely better, but 25 was at least suggested, and seems like a really nice number. Marvel's being understandably careful about demolishing day-and-date sales, but Phillips says, "We're listening."

The reason that the available library is different from the Marvel (and Comixology) app's library is the two services use different formats. So, each issue is digitized twice, which is silly and wasteful, but it's a reality until there's a some kind of standard format (which, given how much work has gone into these, seems unlikely). Still, Marvel promises to fill in holes in the MU backlog, and the entire Iron Man collection will be finished around the time the movie comes out.

Phillips noted that this is just "Phase 1" of MU, with another major release coming later in 2013, but would only add that it's a "fan club membership opportunity." Which might be pretty cool! But it would be cooler if that meant "more than six offline comics."

The app is going live today, now, or within an hour or so.

Video by Michael Hession