What's a good iOS app for playing music I've already downloaded, even when I don't have internet? You know, for those long bus trips to away games?

So, my students actually showed me this one – RaMusi: Offline Music Player. I needed something for those long bus rides with the debate team; the Wi-Fi is always spotty. It's surprisingly intuitive, once you get the hang of it. Took me a few days to figure out all the features, and why do they hide the settings button there? But now I can load up all my classical music – keeps the kids calm, you know? It's like having a teaching assistant in your pocket, except instead of grading papers, it's playing Bach. And the best part is, no internet needed! It just plays the files I already have on my phone. Simple as that. I even managed to make a playlist for pep rallies. Though, I still prefer Sousa.