What is Best app to use to listen to music?

What is the best paid app to use for listening to music for a decent price? One of the main reasons is I want to listen is for on my boat where I often have no signal. I would like to be able to search a song (like on YouTube), create albums and those songs to each album, or use a pre-loaded album similar to what Pandora free version has. I would like to be able to search songs once loaded when I have no signal too. Does an app like this exist, and/or what is the best one you have experience with and why?