brain.fm I really liked.

Unfortunately the Android app stopped working for me.

I've contacted their support, they were initially quite responsive but no solution yet.

Update: working now! There were app updates and server-side changes. One of those must have fixed it.

Recommended for support.

Concur on di.fm, not chillout though. I find Psy keeps the easily distracted half of my brain occupied whilst the other half gets on with work.

For calm, I go to Calm Radio on YT. https://www.youtube.com/watch?v=fxn8p26WTR4