Did anyone had a same feeling about unlock a screen?
I use my nexus 5 and time of reaction - click a power button to switch on screen takes not even one second was reacting so fast that I can't even say how fast it was but in case of my new device which is Samsung s5 is takes while longer !!! And I check with power button and home button. Now I don't know if that's problem with my device or some one else have same feeling.
This seem to be a hardware/firmware problem. Some of the remedies that have worked for me are: 1.) Turn off auto brightness. 2.) Use a smaller SD card, 16 gigs or less.
Check your battery graph. Is there a constant blue line underneath the graph, if there is, like on mine, I was told it should not be there! I have heard that the only time the blue line should appear is when the screen is on. I am still researching this information but many heads are always better than one.
Interesting you mentioned using a smaller SD card. I just replaced my 8 gig card for a 32 gig card and that's when I noticed the difference. Why does that affect it though? This phone should be able to handle 128 gigs! I really hope this is software related. I never use auto brightness, so I know for a fact it's the SD card that's causing.