Hi,
So I have had a Phillips android TV for a couple of months and when I first bought it had nothing but problems trying to open any freeview associated apps, Netflix, Prime, YouTube etc all worked fine. However, when opening the likes of 4OD, ITV Hub I was met with a black screen. After nearly returning the TV, throwing it out the window and putting a hammer through the screen I think I have found the solution....
If you're having the same issue above, go into your network settings on the TV and change your network settings from DHCP to Static IP. I didn't have to mess around with the static IP config underneath.
Clicked onto 4OD and that worked, loaded in lit 2 seconds. Same again with the remainder freeview apps.
Hopefully this solves your issues as it did mine. Seems soooooo stupid that the out of the box settings creates issues with apps???
Sounds like your DNS IP settings. Check the primary and secondary DNS settings in the DHCP section of your router configuration and set them to as provided by your ISP. If you don't know them then try 8.8.8.8, Googles public DNS server.