Just to let you know how my experience has been after "upgrading" to Lollipop on my Z2. I feel the battery life dropped. Not by 75% like most of you are experiencing, but I lost fairly 30-35% of life battery depending on how much I use it over the day. I had set the Stamina mode to something a bit more saving than I used to, and I have to be honest that the battery life on stand by actually improved! Not much, but I can guess the standby battery life got better by something like 15%. But it the other hand, under use, even checking messages, the drain got considerably faster, almost twice as fast. The discharge curve seemed to change a bit as well as it seems to drain even faster below 20% of charge. Under use, it goes like 20>15>7>2% in minutes...
Well, this is just to share my experience that the standby battery life improved by some 15% while under use it got like 40% worse... I think at the ende of the day (when I reach the end of the day...) I lost overall maybe 35% of my previous battery lifetime.
I actually have no hopes to find a solution for this as nothing moves me from the idea that this is on purpose to make you buy a new phone. Motorola is the champion of doing this, their high-end mobiles becomes useless as battery life drastic fall after one year of use. That's the main reason I switched for Sony after 15 years using exclusivelly Motorola mobiles. My expectation turned true to discover the almost unbelievable battery time the Z2 had... Just to discover that Sony, sooner or latter, or to be more specific, after the Lollipop, would do the same to make me buy a new product. The Z2 had an awesome battery life even after one year of use, until last week when I did the "update". Now it is just another useless smartphone.
Thanks Sony...
