It is definitely NOT a whatsapp issue. I use whatsapp a lot and my battery is just fine.
If you have whatsapp problems after installing 8.1 + cyan I recommend deleting whatsapp -> soft reset -> re-install whatsapp.
It appears the majority are exactly opposite to your experience. Is there anyone monitoring this board who really gives a crap about this problem of horrible battery life?Just wanted to mention with regard to battery that before I installed GDR1 for 8.1 with Cyan, I consistently got a super-hot corner near the top right, even if I was just browsing the web. It was really, really hot. Since 8.1 GDR1, that hot corner has now become a warm corner and the battery is better, but not wildly better.
It appears the majority are exactly opposite to your experience. Is there anyone monitoring this board who really gives a crap about this problem of horrible battery life?