well after a month and a z5p change (camera fault) this i my experiece
battery:for me i very good. my z5p is paired with a pebble time steel and a fitbit hr and when i'm in car with my garmin by smatphonelink. i power up at 8.00 am and the batter...
yes i've got random disconect but i think it's a bluettoh problem cause i've got random issue with other bluetooth device.
And yes sometimes, luckly only few time, i've got some strange battery drain and phone become hot as hell.
hope with 6.0 son...
for a very good case look here http://www.tetded.com/home/en/339-xperia-z5-premium-e6853-z5-premium-dual-e6833-e6883 no magnetic flip but excellente materials and great look i bought the Dijon II (Venus: Black Croc/Toffee ) version and with my gol...
the problem is that sony lock the relusolution of the camera.
we can go over 8mp only with the stock sony camera app
yes it doesn't matter about witch smartphone you have, you can pair it with any one.
my g watch is paired with my xperia z ultra (i'm waiting my new g3) and it work great