I've actually seen my phone take a disappointing step back with the update to 5.1.1. I've had it around a week and battery drain has crept up again, Textra is running into all sorts of issues (for an app that never so much as stuttered before, it has nearly become unusable at times). Just this morning it drained 38% in a little over 2hrs. I'm sure a restart will clear that last piece up. I've also found the modem to be borderline atrocious. Multiple times a day I need to toggle Airplane mode just to get a LTE signal at my desk (which is generally a 4 bar thing) because if it "sticks" in 3G, the 3G at my desk is virtually non-existent. It's great on LTE, just doesn't get back there a lot of the time.