Originally Posted by ylexot
And I guarantee you that any device (BlackBerry, Nokia, whatever) that will sound an alarm while "off" is not actually off.
How can we claim on your guarantee?
Seriously, that's a very interesting point, and I suppose it depends upon how we say a "device" is off. Clearly when a Samsung Android phone is off, the entire device appears very
off. Inside a Nokia device I would hazard a guess that there must be some separation of functions within the device, at an electronics level. A Nokia such my E71 will not do anything when it is powered off, and the primary OS is not active (demonstrated by the long boot time at power-on ). However there has to be some sort of clock circuit that is active and maintains the current time and moreover the alarm time, plus this must have the ability to power-up enough of the rest of the phone to sound/display the alarm.
Coming back to the Samsung, it can't be completely "off" either because then the clock would lose the current time, and I haven't noticed that happening. So the clock circuit must surely be active, and "not off". What's missing is the little bit of electronics to turn on the audio and display (and possibly store the alarm times in a non-volatile memory).
So for me, it's really down to the phone being "off enough" to save battery, stay silent, but still sound a wake-up alarm! Shame it can't be an out-the-box option. I'm definitely going to try the helpful suggestions of airplane mode and the alarmdroid utility. It is quite possible that with those options in use phone nirvana can be achieved!