Be aware that even if there is in-seat power it may not be sufficient to power certain devices. I was on a 767 (not sure which one, it's the one with 5 rows of 2-2-2 seats in F that most people dislike but I found just fine), and the in-seat power plug was not sufficient to power my laptop. YMMV. I would not count on the in-seat power for anything critical.