I updated my Samsung Galaxy S5 with Verizon's Lollipop update. I immediately noticed a general sluggishness. Folders could take up to 2-3 seconds to open. Applications such as Microsoft Outlook could take up to 7 seconds to open. Wifi seemed to drop fairly easily within our home. Prior to the update, the phone's speed and connectivity were very good.
My battery life also went downhill quickly. Prior to the update, I could use my phone all day and it would rarely get to 70%. With Lollipop, it quickly went into 40%. I also noticed that my usual trick of recharging it quickly by entering Ultra Power Saving mode didn't do much. In or out of Ultra Power Saving mode, the phone was recharging at a rate of approximately 1% per 10 minutes - significantly slower than it recharged before. If I used the phone and it was recharging, the battery continued to drain.
I did quite a bit of searching on various forums and determined that I needed to do a factory reset. Many people seemed to believe it helped substantially. Others indicated that they still had issues.
I reluctantly performed the factory reset last night. I am happy to say that performance is much snappier today. And my battery life is significantly better. It seems to be on par with what it was prior to the Lollipop upgrade, which I considered excellent.
Amazon's Kindle application doesn't recognize the dozens of ebooks I have stored on my SD card, although Kindle downloaded them to the SD card and had no problem recognizing them before the factory reset. Kindle won't allow me to change the device from the one that the Amazon Kindle application assigns. Essentially, it believes my phone is a new device, not one I had previously had. There doesn't seem to be any way to tell Kindle that my phone is one that I already have a profile for. Amazon's Customer Support doesn't seem to know what to do about it. Amazon Music, Amazon Audible work fine and recognize my music and audio books on the SD card.
I have also found that the Auto setting for Display Brightness is very inconsistent. At times, it seems to work fine and adjust properly given the available light. At other times - even in the same light and without moving the phone - the display is far too bright or too not nearly bright enough.
Verizon and the others should come out with some advisory regarding the right way to proceed with the upgrade. I suspect people should do a factory reset before upgrading to Lollipop. Performing a factory reset after the upgrade certainly seemed to help quite a bit in my case.