Over the last month I've had somewhat of a binge of buying phones from Amazon and returning them for one reason or another and I've noticed that the first 1-3 days of phone ownership are usually the toughest on the phone / battery.
I've owned over the last 2 months (in order):
- HTC One (x3 as 2 were faulty out the box)
- LG G2
I've decided on the N5 as being the best for a number of reasons, but my favourite is price.
I havn't worked out whether it's a combination of new phone = more usage or new phone = requires battery calibration. But the N5 is the only device out the major players that actually made it through day 2 (the day after it came out the box) without a charge midway, infact it's ONLY JUST gone on the charger after some 28 hours of moderate (3 1/2 hours screen on) usage.
My gut feeling is that once you're out the first week just use the damn thing, but the first few charges can make a difference to how quickly the battery feels calibrated. My N5 came with 50% charge out the box, I ran it down to 0% and topped up charge as much as I could the first day. Once I got home I once more let it 0% and then did a full 0-100% recharge. Then my 28 hour experiment started and now I'll just use it as normal, and not worry.