Who uploads music files to Soundcloud and aims to be available on the mobile internet should try Appy Pie. Appy Pie is an app builder enabling to create mobile apps without the need of programming skills. It has an integration with Soundcloud to get the content into the app and does provide a comfortable service at all by being compatible to all common mobile app platforms. The service is available in a free and various premium versions to be distinguished by prices and features. To learn more visit Appy Pie.
The Audio Silver Lining blog has published an article with a review of mobile applications and software to create music. Even by natural restrictions regarding the size of the surface some of these applications have the complete features of a studio software and may be useful in particular situations: Mobile Platforms & Music Production.
Similar services are available at online music software.