Cross Platform Music Streaming

[tl189]

Hi Spotify community.

For a university project of mine, I am examining if there is a capibility to develop a cross platform music streaming service that would integrate ones Spoitfy library with soundcloud, iTunes etc... I have seen a number of apps that claim they do this already, such as Mergify etc... But being a poor student my funds are low, thus I cannot buy the app. If anyone out there uses it please let me know how it works and its good/bad features? 

Also is there anyone who can shed light on if a cross platform streaming service would actually work with Spotify? 

Any comments and/or ideas would be really helpful. 

Thanks