As mentioned it's a case of the app not working with the latest versions of android.
Also called customer services which was a bit of a laugh. First chap I spoke to didn't really do or say much but went to speak with the "techs" and I was suddenly put through to another chap who was all over the place. Firstly he asked for my password, when I told him I wasn't giving him my complete password he then asked for the 3 characters. Got me to do the whole "turn it off, turn it back on" even though I told him I had done this several times and re-installed the app. He also got me to try ITV as the app might not get BBC channels as they had their own player (iplayer), utter nonsense.
Anyway after 20 minutes of repeatedly telling the guy it was a Nexus 9, running android 7.0 and not a Nexus 7 (which he kept saying) he apologized for forgetting to tell me anything over 6.1 wouldn't work. His coup de grace was trying to get me to believe that "android had put out an update without telling virgin" as if they'd done it in the middle of the night. Told him that these updates were common knowledge and even Joe public knew about them months in advance. To be fair he just kept on with the same bare faced lies as if he was talking to an idiot.
So, my first experience of virgin media customer services would seem to be like lots of other people's experience, very, very poor.