Default Disabling cellular, and force power off at certain %?

Hi guys,

I can't seem to find anywhere in this device to force cellular off. I don't want to enable aeroplane mode because I use wifi and GPS.

Also, is there a way to force the device to power down when it's at, say, 8% power? It seems like it powers down when it's totally drained, which causes the device to stop tracking time when it powers back up. I imagine if it could force power down earlier, it would still keep time when I get around to recharging it...