[Droid Ultra Q&A, Help & Troubleshooting] Jumnhy:
Battery drain has been a relatively common experience after the KitKat 4.4 update. I have a Droid Mini, not a Maxx, but I've been seeing a lot of reports for all three of last years Droid line (Mini, Ultra and Maxx). Troubleshooting battery life is typically done through looking at events called wakelocks. Wakelocks are created by apps on your phone to prevent it from going into "deep sleep"--basically, they allow the CPU to stay on when the screen on your phone seems off. BetterBatteryStats or WakelockDetector are two apps that can be used to gain a little more insight into what wakelocks you are experiencing and what might be causing them.

However, wakelocks are broken down into two categories--those run by the Android kernel itself (kernal wakelocks) and those created by apps running in the background (partial wakelocks). Unfortunately, the 4.4 update made it impossible to view the partial wakelocks directly without root permissions. If you did as I did and naively updated to 4.4 without root, you won't be able to root your phone (as of now) to see the partial wakelocks. Instead, the wakelocks will show up under the kernal wakelocks that can be viewed--but instead of an app by app breakdown, they are visible only in the aggregate, so figuring out which app in particular is causing your problem can be a real trick.

One way to do so is to look at the apps running in the background of under the "Apps">"Running" in settings and see which apps you have actually been using and are supposed to appear and which apps are not. Then select the apps that you didn't start and force close them in sequence, checking Wakelock Detector or BetterBatteryStats after each to see if they have fixed your issue at all. The best way IMHO to see if they had an immediate effect is to look for increases in the "Deep Sleep" stat--if the app had been keeping your phone awake, and you force closed it, the Deep Sleep time should go up after you shut off your phone.

All that being said, troubleshooting is a real *****. There is an abundance of non-app-related issues with 4.4, or so it would appear. I have seen posts attributing fixes to turning location services to "GPS only". Others recommend clearing the Google Play Services cache in the Apps menu, clearing the cache in phone more generally, and using every other more conventional battery conservation trick in the book. Still others reported the only fix as a factor reset. These things had little to no benefit to me--although I never had to resort to a factory reset since I found a fix this morning. For me, all it took was going into Wifi>Advanced>Wi-Fi frequency band and changing from "Auto" to the 2.4GHz setting. This seems to have nailed the persistent wakelock issue that had been showing up as "Android OS" under the stock battery life in the settings, which showed up as a kernel wakelock under "suspend_backoff" in BetterBatteryStats. Hope that something out of all of this can help you--I'm immensely frustrated with how poorly my phone performed for the last month after the KitKat upgrade. It appears, however, that the fix I just found has restored my battery life from the 3-6 hours I have been getting lately to 12-14 hours. I'll update in a couple days after I see how things go. Best of luck!