If I use my 2018 iPad at full brightness, the battery really doesn't last very long - 4 to 5 hours. Turning the screen down greatly extends this, but I sometimes watch movies on the porch during the afternoon and need full screen brightness. This is my first iPad (but I've had Macs since 1985 and iPhones since 2009) and I was rather surprised the battery didn't last longer. My 2013 11" MacBook Air runs almost as long and it still has the original battery.