|Google wants to submit an All Access app for iOS, but is still working to find something Apple will accept at the App Store, say 9to5Mac sources. What disputes the companies might have are unmentioned, but they could conceivably involve things like the revenue split from in-app purchases, and/or features that may violate App Store guidelines.
In the meantime, one of the most popular third-party Google Music clients for iOS -- gMusic -- has added All Access support. That includes the ability to both create and play stations, and add music to a library from within the app. Users must still have a paid All Access subscription.
Apple could in theory be hesitant to allow All Access because of plans for its own streaming music service, and its increasingly hostile stance towards Google. At the same time, though, streaming services like Spotify, Rdio, and Pandora are already on the App Store, which could make it difficult for Apple to defend rejecting Google. The latter also has other titles on the App Store that compete with Apple, such as Chrome and Google Maps.