We perfected it with the addition of copious sweeteners and ice <| sep |> I always suspect misbehaving apps if battery life was great then starts to degrade after installing a lot of apps . Degradation isn ' t usually linear , but sudden after installing certain apps . Its just that we don ' t notice right away so don ' t associate it with that particular app . I know its a pain , but wonder what would happen if you tried hard reset , waiting a day or two for updates to settle down and not restoring apps for several more days after that to get a benchmark . Then try installing one app every couple days to see what affect it has on battery . I don ' t expect typical users to go through all this trouble . But it would be interesting if some enterprising Insider or Windows Central or , Godforbid , Microsoft themselves did some testing like this and published results .