Offline music downloader?

So I'm just wondering do you guys know any apps that let you listen to music offline for iPhones? I have one but it got deleted and I can't download any more songs on it. I find a lot of apps with good ratings but they have to have Dropbox and Google Drive and I don't have that. Does anyone know apps that don't require that and also download music to listen offline? Obviously I need internet to actually download the songs but listen to them without connection is what I'm asking. Please, I'm at a dead end lol. Hope you guys have a nice day btw! <3

IPhone 5s - Won't turn back on?

Shortly after using my phone I put it on standby mode. I went to turn my phone back on and there was no response.

My phone then heated up for a short space of time.

I have tried charging my phone. However, prior to it not responding it had been charged fully.

Not sure if there's any fix. Looking for some help on what I could do.

Added (1). Edit: Whenever I try and turn it on my home button heats up

Why isn't my iphone turning on? - 3

I have a iphone 4s that i haven't used for about 2 years and was going to sell it. I put it on charge and the battery sign came up so i left it for a while to charge but it was still saying it had no battery. So i left it for a few days and now when i unplug it it just comes up with the apple sign and doesn't turn on. I've tried holding the lock button down whilst plugging in and re starting it but notbing is working, Does it need a new battery or is the phone broken?

Can I put my current pay as you go SIM card in a contract phone?

I want to get the iPhone 6 on contract but I want to keep my number. I'm on o2, so if I go to on o2 shop and ask them if I can keep my number will they let me do it? What is the process of it all because this is the first time I'll be getting a contract phone

IPhone recovered twice, still not working?

Recently my iPhone 7 has been turning on and off, with the apple logo flashing on only to go back to a dark screen. This has happened before, and I had to go through iTunes and restore it in order for it to work. Well I tried to do the same method again, two times, but its doing nothing! What should I do?