On the top and on the right is the lock switch. --edit-- Bump fpp

Also note that with this switch set to locked, when you slide open the keyboard the lock option is temporarily overridden and the device is activated but as soon as you close the keyboard it returns to the locked state. Quite a neat feature

The only problem with this particular lock switch is it's fiddly to operate, I actually dropped my N810 today whilst operating this particular switch. (Damaging/cracking the case and stand on one corner slightly)

Really do think we need some form of hand strap on the N810 whilst on the move to prevent dropping when opening and closing keyboard and operating tiny switches with big fingers.