I may be be mistaken but I believe the default runtime environment for Kit Kat is Dalvik while the default for Lollipop is ART.  The migration of apps from one to the other is not smooth for a lot of folks and I think this is what may be heavily contributing to problems when a factory reset is  not done after the upgrade.   After reading so many Lollipop horror stories I was so very skeptical myself and didn't want the upgrade but I went ahead and applied it to a new G3 and then immediately did a factory reset.  It has worked flawlessly so far with no lag, random restarts, etc.  
I write all that to say this, I know it may be a irritant but a factory reset after Lollipop is highly recommended.
from the Note Edge
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			I write all that to say this, I know it may be a irritant but a factory reset after Lollipop is highly recommended.
from the Note Edge
			
				Last edited: 
				
		
	
										
										
											
	
										
									
								
	