Dear oleson11 & (edras), I really feel for you & empathize. Mine was one of the 1st phones that received the 5.0 update (i'm talking about Lollipop, of course). Messing around with my phone became a full-time occupation for months. I have gotten it to work 90% of the time, which is about as good as it's gonna get with the S5 / lollipop. I'm terrified to install the latest software update until i know for sure what it is. I wish to God I had paid closer attn instead of just hitting 'install' bc I never would have gone ahead with that. So - here is a list of actions I took over a period of 2 months of trial & error. Having been through it I can save you the grief, trouble & anguish I experienced and list them in the order of most effective. Please note: you have to do ALL OF THESE ITEMS for any hope of getting a semi-smooth operation back out of your phone. AND - don't do a factory reset on your phone. it doesn't solve anything. It may get you a 1-way ticket to the rubber room a bit quicker, but it won't make your phone work any better... you still have to reinstall all your stuff & that, in & of itself, is another 2 mos worth of grief right there trying to get the damn Vzw Cloud to sync up correctly. So, here's the list:
Just a note, after you go through all the below steps you should keep an eye on the phone. I had to clear cache, remove battery routinely for a while until the phone completely resets. A good rule of thumb is: if the phone starts acting weird on you, pwr down, remove the battery for a few mins (sometimes I just take it out overnight). Or, re-start. but, re-starting the phone continuously caused defragmentation, which means your going to have to clear the cache just as much.
But, I just checked and the Android system is using 3% of my battery, the OS is using a miraculous 1%, as opposed to the 30-50% they were using before I did a complete overhaul. I have 91% of my battery left since 8am this morning (its' 8.5 hrs later). total OS usage 8%
#1. take the phone apart. remove the SD card, if you have one. take the battery out & let it set for at least 10 mins (cold to the touch). This will 're-set' auto refresh the phone. Don't reinsert the SD card. Leave it out. if you have to, transfer stuff onto the phone (apps) or computer (pics).
#2. Begin by uninstalling as many utility apps as you can. If you think you need to, make a list off all the apps you have to make it quicker when you go to re-install. I got rid of every non-essential, non-credible app i had including SnapChat, other cleaner & security apps, social media apps (i only re-loaded a few essential apps such as: fb & pininterest, fb messenger, some bank & credit card apps that are usually sourced by better developers.) Basically, I stripped the phone down to as close to factory settings as possible.
~ Also - I DISABLED (Uninstalled) as many apps as I could that I wasn't using. Such as: NFL Mobile, Travel Wallpaper, S Health, Video Trimmer... Amazon apps that i don't use (Kindle)... just go through all your apps & force stop / uninstall. you can always enable. but a lot of those just constantly run in the background, draining your battery.
#3. Next start clearing caches. Clear the Phone's cache by following the above instructions (hold the volume up, power on button & home key all at the same time. As soon as the phone 'wakes' - 1 quick vibrate, release the pwr button. keep the volume up & home key depressed). There will be instructions at the top of your screen to use the Volume Up/Down to scroll & Pwr Key to select. Select "Wipe Cache." At the bottom of the screen in yellow text a msg appears saying 'cache wipe successful'. Repeat. (i was told to always do this 2x when performing this operation). Then 'reboot' the phone.
#4. Then Clear individual app caches (be careful to NOT clear data) for your contacts, messages, calendar... anything that has been giving you problems. You do this by going into the app through App Mngr. You have to stop the app 1st before clearing the cache. your weather cache is a good one to clear.
#4. After your done de-cluttering and cleaning your phone, pwr down again, remove the battery to reset it, then clear the PHONE's cache again. Power down. Then re-start your phone as regular.
#5. If you're using Verizons Msg+ app, GET RID OF IT. Go in and switch (app mngr) your default messaging app the the factory installed Samsung Message App. It's just a plain msg envelope with a yellow flap. after you ENABLE the default msg'ing app, force stop Message Plus app, uninstall it. Its a Vzw add-on. They want you to use their app bc it uses up data ($$ for Vzw) but it also doesn't run as smoothly with the new OS upgrades bc when Vzw rolled out their Lollipop 5.0 they didn't account for their unique Vzw features as far as tweaking the Samsung upgrade. Verizon won't tell you this (everyone lies, what can we do) but Samsung releases the software upgrade to all the major carriers who then add their unique codes to coincide with their system (you've heard of 'locking the phone' or 'rooting' a phone). Verizon is usually pretty good with this but in this case they got sloppy. Of all the networks that got the upgrade back in March the Vzw network has had THE most problems. just a sidebar.
#6. Then, pwr back down, remove battery.... clear cache.... think of pwring down the phone as your computer or internet browser window. sometimes you have to close the browser entirely after you've changed a setting for it to take properly. If you make major changes to how you use the phone, re-start it. clear cache. I wouldn't get to crazy wi/clearing the cache after you get things set back up the way you like them. but, just maybe every week or two. it's also a good idea to remove the battery from the phone. Some ppl i've talked to do this nightly. I have no expertise on the subject as far as frequency... so , you can look that up if you want.
#7. Leave the SD card out of the phone entirely until you start to see how it's working. Add apps back on SLOWLY. twitter / fb use a lot of RAM. email apps.. too... this is what causes that horrible lag time when opening apps, if there isn't enough RAM to run everything. i only have about 10 apps on my phone now that constantly run (push services).
#8. After about a month I re-inserted my SD card. it seems to be okay. I do occasionally get these weird msgs about my com.svc stopping, my contacts... but it seems like that's part of the glitches with the 5.0 that mbe hopefully will be fixed in 5.1. Who knows. I just hope I don't have to completely re-vamp my phone again any time soon.
I now know more about phone tech then i ever care too. and i'm sure, after reading this, you feel the same. 
Sorry for the huge reply... but, this is what i had to do & it's lengthy to explain in an 'email' format.
My phone is better. I will say that.
Good Luck!!
