[1] http://en.m.wikipedia.org/wiki/Covert_listening_device
[2] http://news.cnet.com/2100-1029-6140191.html
[3] http://www.schneier.com/blog/archives/2006/12/remotely_eaves...
[1] http://en.m.wikipedia.org/wiki/Covert_listening_device
[2] http://news.cnet.com/2100-1029-6140191.html
[3] http://www.schneier.com/blog/archives/2006/12/remotely_eaves...
Some handsets can't be fully powered down without removing the battery; for instance, some Nokia models will wake up when turned off if an alarm is set.
I'm not so sure that this is still a common practice for modern phones.
Does the iPhone/Android phones do this?
If my Android phone is off, it's off. It doesn't turn itself on, period. If it's just idle, screen off, with lots of stuff asleep, sure it will "wake up" in that the screen turns on, and sound an alarm. But that's it.
This is done commonly by builtin services.
May be useful in business surroundings, but this makes the iPhone an awfully bad travel alarm.