the battery goes from 100% to 99% in just a minute.
and the navigation bar of my 830 has just stopped functioning. First the search key stopped working and now the entire bar is not working.
And my phone is just 5 months old.
You could have a faulty handset which is something I'm wondering about mine, have/had similar issues as yours but not near as bad... From all my reads I'd say Nokia missed the mark on this phone in regards to hardware, since haven't had an updates since Sept 2014 to see if that may help all I can go by is the hardware.
Can fully charge my battery (100%), turn off my phone then turn it back on in 15-20 min and it is down to 96%, sometimes it can be as low as 94% but never any lower no matter how long its been off, it's like the top end of the battery is wonky... Battery drain isn't too stellar either in my opinion, my Ativ S and 1020 are considerably better.
My capacitive buttons have gotten a tad better over time which is strange as nothing has changed, back button was the worst in the beginning.
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