Tunemark works by reading and controlling the currently playing media from Android's media notification. This allows it to work with most music apps as long as they show the currently playing media notification.
This is my first ever Android application and it has been fun learning some native app development. I have some features planned for future releases such as sharing bookmarks via a link and perhaps a companion app for smart watches.
Hopefully you find this interesting and if you or someone you know could benefit from it, please give it a try or let them know!
I'm happy to answer any question and hear any feedback you have on the app or the product page etc.