I don't know for sure but it almost seems like wp8 is a complete rework of the os. Like they threw out all of wp7 and started over from scratch. If this is the case then they wrote a whole new os in a very short time compared to wp7. Hence why some things have appeared to taken a step backwards and some compatibility issues between wp7 apps and wp8.
Sent from my Nexus 7 using Tapatalk HD
I had this issue for weeks and one of the suggestions from the Nokia forums that helped was the re-enabling of all disabled background agents from the Settings page. Then going to the app list and opening every app that was listed in there (and closing it down before opening the next one). Since doing that last night both Simple Calendar and Weather Flow are updating normally. Note, when you have re-opened 15 apps you get a little warning message, but I carried on regardless in a bid to flush out the suspect app!
Live Tiles no longer updating after firmware updat... - Nokia Support Discussions
I didnt understand. My Me Tile isn't updating. I am sure it isn't an "app".
apologies, I was replying to the person above who stated most of the live tiles weren't working and failed to quote the appropriate post