I use
Private Internet Access.
I've been very happy with their service.
It works through apps for all major OS's. I have the Windows and Android (on my phone and Amazon Fire TV). They all work prefectly.
Never had any speed issues, and you can select servers from all over the world to connect to. I used to use that feature to watch iPlayer in when I was in Norway. Unfortunately the BBC has added their UK ip address to a black list so that doesn't work any more.
I love the mobile app though. I won't use public wifi without it.