I just hate the battery life problem. Which is another reason every top tier phone should d have a replaceable battery.
I've used iphones, evos, Droids , galaxy S 's, ones, lumias, pl Windows and aside from the droid RAZR MAXX series, that's the only phone that lasts a full day without recharging under heavy use.
Unless you count the phones that don't do much like blackberry or palm Centro.
All this innovation in smartphones, so any new features but no day long batteries.
Has it improved? Yes.
Had an evo 4g for a while and while it was a great phone for its day (first 4g phone, first phone with a FFC, first phone to introduce video calling to the masses, but one huge drawback - battery life was terrible even with a custom rom.
I was getting 6 hours when the phone was new, then after the first year between 1 and 2 hours. (realized later HTC is just terrible with battery capacity after the first year) and I had to walk around with 5 batteries and an external charger all day to keep y phone working.
I had an iphone 4 alongside it with AT&FEE and while I got better battery life by far, I couldn't keep a signal (I'm sure you all remember the antenna situation and instead of apologizing for their faux paux jobs made excuses "you're holding it wrong"
Overall at that time I was happier with iPhone than android but i still kept both because I liked the customization of Android and the battery life of iphone.
Battery life has improved but not nearly enough