Apple is reportedly still ironing out details with publishers regarding an upcoming newspaper and magazine subscription service for the iPad and iPhone.

Apple is reportedly on the verge of launching a subscription service for paid apps, and the company appears to be ironing out some final details with publishers who plan to participate.

A number of European newspaper and magazine publishers have been contacted by Apple and informed that they cannot offer free subscriptions for iPad editions through the upcoming service to customers already paying for a print version of their publication, according to a report in Dutch newspaper De Volkskrant. In other words, once this subscription service finally launches, don't be surprised if your favorite magazine does an iPad edition and you have to pay for it again.

The report says this will go into effect after April 1. The Belgian, Flemish, and Dutch publications quoted sound none too pleased. They're also unhappy that subscribers will have to go through Apple to sign up for any iPad-edition publications.

Those gripes aren't new: the Financial Times said early last year its own discussions with Apple on the topic nearly fell apart over the issue of who owns the subscriber records, Apple or the publication.

Apple has reportedly been working on such a digital subscription service for its mobile devices for more than a year. Many expected Apple to announce the service with the introduction of the iPad in January 2010. Instead, Apple only announced partnerships with book publishers who would sell books through Apple's iBooks store.

The service was scheduled to launch next Wednesday, but as of last night has been delayed again for several weeks. Its official unveiling is set to coincide with the introduction of News Corp.'s The Daily, an iPad-only newspaper. The event will be held in San Francisco and Apple CEO Steve Jobs is scheduled to take the stage with News Corp. Chairman Rupert Murdoch.