Music playlist sama ke tidak. STAMINA mode ada on or not. And by the way compare with an android phone la why with apple its different OS la bro. Both system voltage is different calibrated with their system and IP4 is a Single core smart phone manakala Xperia ZL is quadcore sure eats more battery la.

Etc i bawak Ferrari compare with your Kancil see which car drink more petrol.

Then he said that Sony not good as Apple? JK

at what pecentage the charging stops?

Here's what i found

different cable warrant different charges

This can be seen on Samsung galaxy with the galaxy charging app installed

Tested on Note 2
Sony Ori cable + Sony 1.5A Charger = ~900mA
Sony Ori cable + Samsung 2A Charger = ~1800mA
Samsung ori cable + Samsung 2A Charger = ~1200mA (cable might be problem already)
Sony Ori cable + YooBao YB637 1A = 1100mA
Cheap 2 meter flat cable + Sony 1.5A charger = no charge or sometimes 300mA
Cheap 2 meter flat cable + YooBao YB637 1A = No charge

so get an ori thick cable from whichever manufacturer

USB 2.0 is @ 500mA to start registering charges
too low the phone might not let it charge
USB 3.0 can supply up to 900mA charges

try change the cable and see
borrow from your fren see if it helps

I already broken 2 cable
(granted one is chaplang cable, another is yoobao ori cable)

but the point is
cable is the main culprit of most charging problem
as they are soft and pliable, thus easy to be damaged