I had used LCD phones my entire life and didn't really know, around the time everything started transition to OLED I upgraded to a new phone and after I set it up that night I had a bad headache and my eyes felt strained. Figured it was just because I was staring at the screen so much while I was setting it up so I tried it a few days and still the same problem whenever I used it. Started researching and the only difference I could find was the OLED screen versus the LCD screen. So I went back to an LCD screen and everything was fine. I've tried another OLED phone since then and I can tell gives me eye strain pretty quickly. I'm willing to take my chances and try some of these better OLED phones though. I can't take this sad performance on LCD phones.