My first tablet, the Xperia Z1 Tablet, was amazing. On standby power it would last without being plugged in for weeks with barely any charge lost.
The Z2, on the other hand, is practically trash in comparison. It burns through it's power way to quickly, but not just in standby. No, the REAL problem is that when it is physically turned off the splash screen turns on every few seconds until the battery dies. It always goes from 80% to zero within an hour if turned off, but will last maybe a day if turned on with the screen turned off only because the screen doesn't turn on constantly while it's on. I've never been able to charge to 100% because of the issues with how it uses power.
This of course means that it is the WORST device to travel with, and every so often I will be unable to use it for days at a time because when it does finally run out of power it cannot charge properly without being already having some power.
Just a few days ago, I unplugged it for use in travel. I barely used it at all, but it died. I then plugged it in, and a day later it was at 50% then a day later 28% - still charging though. This is of course because of the way it constantly turns on until the power depletes. There's no way to turn this thing off in a way that keeps it from draining it's own battery.
Now it's dead completely, won't even charge. This has happened before and when it does it might take a few days to a few weeks plugged in before the red light will actually come on.
So while my positive experience with the Z1 is why I bought a Z2, my negative experience with the Z2 and a Z5 Premium is why I swore off ALL sony devices going forward. That, and the fact that I can never get customer service as an American customer. I REFUSE to buy any branded models, given serious problems with that in the past, so I import UK models that work just fine in America, except that Sony doesn't stand by it's products in America.
At this point I'd just like to find some way to get some life out of this tablet. I mean, is there any fix to any of these problems? Any way to keep it from flashing that splash screen while it is charging? It should only ever do that when I physically touch a button! I'd love to be able to turn it off without the phone dying. Who ever heard of a device that dies faster when it's off than when it's on!? Or how about some energy saver mode like we get in the phone models, that disables everything except the very minimum of what is needed? Really, anything that I can do to make this tablet continue to work for me without dying so quickly would be great. Otherwise, I am seriously considering downgrading to the Z1 since that is apparently superior to any other Sony mobile device I ever used, but of course that would mean incompatibility with the latest Android firmwares (and upgrading the firmware doesn't fix the problems, it just makes the screen look ugly)