Get a phone you can turn 'off'...
Don't understand the need to keep a phone on at night - at least one of my phones is timed to switch 'on' at 08:00 and off at 20:30 - if clients need me after that, there's voicemail. It will ring at 07:30 as an alarm without being 'on' as far as calls and texts are concerned... my sister gets miffed if she gets e-mail at 03:00 or 04:00 from some mailing list as her damn phone ((iPhone user) bleeps...
As for those who use Twitter or Facebook before getting out of bed, I'd put some money on it they're mostly female ( BICBW !) ... and if some interrupt sex to answer the phone, then that's good, as it suggests there will be fewer 'slaves to the phone' in the future as the current 'slaves' might not achieve conception so often!