I'm using the same phone but I haven't notice any changes as I still charge my phone once a day like I use to. That's my usual charging but of course depending on my usage like when I take video or play games the whole day then I need to charge my phone twice.
Battery percentage may vary according to the usage (internet, call, video playback, etc..). However, if you feel that the device battery drains quickly when no function is used, please send the device to one of the service centres to discover and fix the problem. www.samsung.com/sa/support/servicelocation/.
